ALBERT

Notes: Summary Glial cells are present throughout the cerebral ganglia ofHelix pomatia, including the nerves, connectives and the commissure. Five types of glial cells can be distinguished on the basis of ultrastructural and organizational features. The topographic distribution of the various types is constant. Two main categories are recognized: 1. Filamentous glial cells (satellite cells of pericarya and axons): The long, thin and ramifying processes of these glial cells surround the pericarya or the axons and form the trophospongia. The ultrastructure and the spatial form of the trophospongia is described in detail. The main criteria of both glial cell types are the lack of organellar specialization, a high content of filaments and glycogen and numerous lipid droplets. A strong linear correlation exists between the index (relative number of glial cells per neuron) of the satellite cells of pericarya and the diameter of neurons in all ganglia, as shown by morphometric methods at the light-microscopical level. A mechanical supportive role and, more importantly, a metabolic function of these glial cells in relation to the neurons and axons is discussed. 2. Plasmatic glial cells (peripheral glia of the ganglia and the nerves, glia of the procerebral neuropile): These three glial cell types are characterized by a rather low content of filaments, particularly in the cell body, and above all by numerous dictyosomes and cytosomes, which indicates a high endocytotic activity. The plasmatic glial cells can be found throughout the periphery of the cerebral ganglia, except for the cortex of the procerebrum.

Notes: Summary 1. Argulus foliaceus possesses two specialized areas on the ventral side of its carapace. They are arranged in a smaller field and in a greater one lying behind the former. 2. The fields of the carapace are limited by narrow cells. They are covered by a strongly sclerotized cuticle. These cells are surrounded by pigment cells. 3. The field cells are characterized by apical and basal infoldings and vesicles originating from its blind endings. Infoldings and mitochondria work together as mitochondrial pump. 4. Nucleus, mitochondria, endoplasmic reticulum, and microtubules are orientated in the same direction as the axis of the cell. 5. In the field cells detectable amounts of sodium and chloride ions are histochemically localized. Sodium ions are found between the microridges and scattered in the ground cytoplasm. Chloride ions will be found too in the microridges and furthermore in the basal infoldings. 6. ATPase-activity can be localized histochemically in the apical microridges.

Notes: Summary The ultrastructure of trichobothria and normal mechanoreceptive bristles has been studied in Microcaeculus steineri delamarei. In spite of great differences in the outer appearance the inner structure of both kinds of sensilla is quite similar: In each case two dendrites are linked to the hair base by a system of fibrils. Therefore it may be suggested that two different directions may be distinguished by each sensillum. Apparently, the bristles may be bent in every direction, but at least the trichobothria show two favorite directions of bending. Certainly the oval shape of the hair base is the morphological reason for this pecularity. The fibrillar arrangement attaching the tubular bodies to the hair base deserves special interest concerning possible movements of the tubular bodies during the bending process of the sensory bristle. Some cytochemical studies are under investigation.

Notes: Summary Argulus foliaceus was put into water containing different amounts of sodium chloride. Various concentrations caused changes in the ultrastructure of the fields of the carapace. Very crude structural changes occured, when Argulus was put without any adaptation into distilled water or into a solution of 1% sodium chloride. When the animals were allowed to adapt slowly up to a final concentration of 0.6% sodium chloride by several steps, only small changes in ultrastructure were observed, mainly reduction of the apical cell surface, appearing of multivesicular bodies, and numerous patches of glycogen in the basal cell parts.

Notes: Summary The tympanic organ of the Cicadidae is situated on the abdominal ventral side stretching inside a cuticular capsule, which is formed as an irregular cone-shaped protuberance on both sides of the second abdominal segment. Near the hearing capsule lies the drum in a cavity spanned perpendicularly with regard to the longitudinal axis of the animal. The drum forms a narrow and flat process reaching in the hearing capsule. The tympanic organ is attached to this cuticular body. On the other side the organ is fixed at the integument of the distal part of the hearing capsule. There are two protuberances, to which the scolopidia are fastened. The tympanic organ consists of about 1300 scolopidia each composed of the following distinct cells: the sense cell, which distally bears the cilium, the proximal attachment cell, the scolopale cell, the cap cell, and a distal attachment cell. Proximal and distal attachment cells mediate the attachment of the organ at the epidermal cells of the cuticle. Numerous folds and much desmosomes associated with microtubules fasten the cells at each other so that the organ is spanned very tightly between the two cuticular bodies.

Notes: Summary Skeleton and muscles of the first and second abdominal segment of severalRaphidia species,Inocellia crassicornis Schumm. (Raphidioptera),Stalis lutaria L.,Sialis fuliginosa Pict. (Megaloptera),Osmylus fulvicephalus Scop. (Neuroptera=Planipennia) are described in detail and compared with some other megalopteran and neuropteran insects. The basal abdominal segments are slightly reduced and provided with a rich musculature. Besides plesiomorphous characters, which attest to the primitive state of the whole group, there were found some apomorphous characters. Though these characters do not permit decisive conclusions about the phytogeny of the neuropteroidean orders they are systematically important. The hypothesis of the monophyly of the neuropteroidean orders (Neuroptera + Raphidioptera + Megaloptera), hitherto almost completely based on symplesiomorphous characters only, is supported now by some presumably derivative synapomorphous states: (1) a transversal suture on the notum of the first abdominal segment which is homologous to the metathoracic scutoscutellar suture, (2) an always medianly divided postnotum of the metathorax, (3) a transversal sternal suture of the second abdominal sternum, (4) a connection of the metafurca with the lateral part of the antecosta of the first abdominal segment by a muscle (M 1) or a tendonlike or sclerotized ligament, (5) a ventral spiracular muscle (M26) between the tip of the metafurca arms and the ventral area of the first abdominal spiracle. All derived characters, held in common between Raphidioptera and Neuroptera and seemingly indicating a relationship, are found in some other insect orders too. Thus they are not or almost surely not synapomorphous. These characters are: (1) a transepimeral suture, (2) a cryptonephridial arrangement of the larval malpighian tubules, (3) the “distance segregation” or “distance pairing” of the sex chromosomes, (4) a spermatheca provided with two ducts, a ductus receptaculi connecting the bursa copulatrix with the spermatheca, and a ductus seminalis connecting the spermatheca with the oviductus communis. Some other derived characters may indicate a sister-group relationship between Raphidioptera and Megaloptera,viz. (1) a postepimeron (causing a lateral stiffened immovable connection between the thorax and abdomen in Corydalus and the Raphidioptera) with a cranial epimeral apophysis (an enlargement of the antecosta lateralis), which is connected with the metafurca by a ligament or a skeleton bridge derived from a furcoantecostal-muscle (M1), (2) a reduced framelike tergite of the second abdominal segment, whose reduction begins in the center of the sklerite, (3) a polyintersegmental tergal muscle (M27) (p. 235), (4) telotrophic ovarioles in a special condition (p. 239), (5) the imaginale gula; 6. the cleaning behaviour. At least the first character ist most probable a true synapomorphy because of its complex condition — almost excluding convergence — and its strict limitation to Raphidoptera and Megaloptera.

Notes: Summary The growth of the coronal skeleton is studied by tetracycline labeling. None of the existing hypotheses on the growth of the sea urchin test is verified. For all plates the ratio of increase was measured individually at the different sutures.All coronal plates grow in a latitudinal and meridional direction. Latitudinal growth exceeds meridional growth, but new plates continually being added at the edge of the apical system. The adaptical plates gradually change their position to ambital and adorai. It is a relative shift, because after metamorphosis thereno re sorption of plates occurs at the margin of the peristome. Ambulacral plates (A plates) are built up of several parts. In unfinished A plates the last partial plate is still growing independently, while the others are already growing as a unit. The height depends on the number of their parts. The ratio of increase decreases in a peristomial direction. Contrary to interambulacral plates (IA plates) the greatest ratio of increase occurs 2–3 plates apicad of the ambitus. There are more A plates than IA plates. IA plates bordering of three A plates become higher to the adradial suture to compensate the increase of the intermediate A plate. There is a negative allometric relation between the diameters of the peristome and ambitus. The peristome issolely expanded by lateral growth of the basicoronal plates. There is on the basicoronal IA plates, an unpaired perignathic elementperhaps homologous to the primordial plate (said by former authors to be totally resorbed during metamorphosis). This perignathic element blocks the interradial growth of the basicoronal IA plates. The perignathic element and the basicoronal IA plates grow as a unit. The natural growth lines of the plates are not considered to be annular rings. The results of this investigation can be carried over to the mode of coronal growth of other families (i.e., Arbaciidae, Cidaridae) only to a limited extent.

Notes: Summary 1. The oenocytes of the larval generation of Tenebrio stick to the lateral tracheal trunks in a narrow chord. They do not increase their number during post-embryonic development, and therefore become polyploid. They are still present in 8-day-old adults; thus a degeneration within metamorphosis does not occur. 2. The following ultrastructural features are typical of oenocytes: a well developed ATER which allows only little room for the cytoplasma between the tubuli. Mitochondria are very numerous, but derived ones could not be observed. There are several free ribosomes sometimes adjoining endoplasmic reticulum to give rough surfaced profiles of ER. A most striking characteristic of the oenocytes of Tenebrio is the great amount of lipofuscin granules which reach their maximum 2 days after molting and are thereafter reduced. At least in the pupa an accumulation of granules take place. One way of degradation runs form scattering to a final exocytosis through the numerous enfoldings of the basal cell membrane. Distinct Golgi areas could not be found within the larval period, but were observed within the pupa and adult period, though very seldom. Acid phosphatases for the destruction of cell particles in autophagic vacuoles become organized in microbody-like structures directly in the tubuli of the ATER, and are transported to the vacuoles. 3. In contrast to other steroid hormone-producing cells there is no synchronization evident within the molting cycle. Also lipid droplets and glycogen rosetts, as a rule characteristics of a series of activations, are not to be observed. The only sign of cell activation is the occurrence of rough surfaced ER-profiles following a reduction of volume. A striking parallel exists between the titer of molting hormones and the number of vacuolated cells induced by a hypoosmolar fixative.

Notes: Summary 1. The Buccal, radular, and venom apparatus morphology and histology of Oenopota levidensis are described. This is the first report on the functional morphology of the turrid radular sac, the first report on the functional morphology of a north Pacific turrid gastropod, and the first histological study of these structures in the Turridae, in which they are highly modified in connection with the envenomation of prey. 2. The rhynchodaeum is similar to that in Oenopota Curricula, except that the rhynchodaeal sphincter is placed more posteriorly. 3. The proboscis of O. levidensis is intraembolic and similar to, but simpler than the proboscis of O. Curricula and Mangelia attenuata. 4. The Buccal tube, Buccal sac, and Buccal cavity correspond quite closely to O. turricula, except that O. levidensis has a. much larger buccal sphincter. 5. The salivary glands are paired and each has a duct that enters the buccal sac. They may function in removing cellular debris from the lumen of the tooth just prior to use. They may also function to initiate digestion, or to lubricate swallowed prey. 6. The radula is highly modified in the typical toxoglossan manner. It lacks a radular ribbon and a subradular membrane. Evidence is presented, and hypotheses are proposed to explain tooth formation. The teeth are most likely formed by odontoblast cells using a cell possibly of inferior epithelial origin as a template. This internal cell may also secrete the base of the tooth and its remnants may constitute the ligament. The tooth appears to undergo a chemical change in the radular sac that may be caused by secretions from the superior epithelium. The tooth may move down the radula supported by epithelial cells which are fastened to the ligament by interdigitating processes. 7. The venom apparatus is quite typically toxoglossan, very similar to Conus, and to the other turrids that have been studied, Lora, Mangelia, Oenopata, Philbertia, and Polystira. 8. The oesophagus is largely an unmodified wide tube as in other turrids.

Notes: Summary The structure of the antennae and the number and distribution of the olfactory sensillae of normal sexes as well as of WZ and ZZ intersexes were investigated by light microscopy. According to the degree of intersexuality the antennae of WZ intersexes are similar to those of females, males, or intermediate forms. There are no indications of a sexual mosaic in the antennae of WZ intersexes whereas the antennae of ZZ intersexes show an irregular sexual mosaic. These results disagree with Goldschmidt's “time-law of intersexuality” but can be explained by a phenotypic influence on the sexual determination of cells.

Notes: Summary The fine structure of two types of glands in the feelers of cave Coleoptera Choleva spec. is described. Both gland types are exocrine and composed of 3 superposed cells: an apical cell or duct cell, an intermediate cell, and a basal cell. The basal cell is the main secretetory cell. It is characterized by numerous microvilli, secretored grains, and developed ergastoplasm. The intermediate cell develops numerous microvilli around the canal. The wall of the canal is perforated at this level, and the space around the canal is filled with an electron-dense substance. Thus the intermediate cell is also a secretory cell. The main differences between the two types lie in the aspect and structure of the secretion in the basal cell and the structure of the canal which sometimes constitutes a bulb. The glands are active in mature adults and are similar in the two sexes.

Notes: Summary 1. Up to this day, there are only a few details known in literature about morphology and mode of operation of the radula of Bythinella. 2. By use of the SEM it was possible to study this microscopic and contrastless radula in detail. Further on the regularity and latitude of variation in the formation of teeth, ecto- and basocones could be discovered for a first time. It was important to find out, that the basocones are not distinct and single cusps on the basolateral crest but the first small prongs of a ledge of the central tooth. The function of this ledge is to stabilize the central tooth. 3. The species of similar lenght as B. austriaca, dunkeri dunkeri and dunkeri compressa have a radula which is relative identical in tooth formation, length, width and the number of ectocones showing only small variations. In contrast, the radula of the greatest studied species, B. bavarica, is larger and there are smaller numbers of ectocones which are also broader. 4. On a simulated edge, the mode of operation, called “Ausflachen” of the radula is demonstrated as example for a taonioglossate one.

Notes: Summary Based on a morphological and functional analysis of the tergal tubercles of the desert woodlouse Hemilepistus reaumuri, 12 types of morphologically and/or functionally different tergal tubercles in terrestrial isopods were investigated. Morphological investigation of Hemilepistus reaumuri showed that the number of tubercles remains constant during ontogeny and that the individuality of the tuberculation as a whole is unaffected by the moult. The morphogenesis of a single tubercle is brought about by locally increased mitotic rates of the epidermis cells. In Hemilepistus reaumuri the tubercles function as a digging device. For the other 11 types of tuberculation the morphology of the single tubercles and their arrangement on the tergites are analyzed. For Oniscus, Porcellio, Ligia oceanica, the granulated species of Armadillidium, and Bathytropa granulata an increased resistance to bending of the tergites is considered as the mechanical function of the tubercles. In Ligia oceanica and the species of Armadillidium this mechanical function serves primarily to increase the effectiveness of a clinging behavior as protection against predators. In Oniscus and Porcellio the primary purpose is to avoid too much water loss by transpiration. In species which can roll up into a ball, such as Pentheus tuberculatus and Polyacanthus aculeatus, the tuberculation has been transformed into an apparatus for protection from predators according to the hedgehog principle. In Stegosauroniscm an increase of the diameter is achieved by the tubercles; this probably also serves as a means of avoiding certain predators. The mechanical function of the ridges in Haplophthalminae, some Bathytropa- and Platyarthrus-species and Buddelundiella could not be found; from a biological point of view the ridges seem to form part of a defense system. Finally the author analyzes the ecological steps that were undertaken by isopods in the course of their conquest of the land and the role the tergal tubercles played in this process.

Notes: Summary Membranous connections within the flagellum are compared, using a basic conceptual (“Grundplan”) and functional model of the antennae of Paraneoptera (Zoraptera, Psocoptera, Phthiraptera, Thysanoptera, Heteroptera, Sternorrhyncha, Auchenorrhyncha). 1. The elastic areas between the segments of the flagellum are not genuine joints, neither morphologically nor functionally. They are membrane joints without predetermined directional movement because genuine hinges (ball and socket) and muscles are lacking. 2. These membrane joints operate on the principle of leaf springs: the hard exo-layer (see p. 141) and the soft endocuticle slide over each other during bending. 3. The functional relations within the endocuticle are quite analogous (lamellate structure; the zones where the lamellae touch and slide against each other react selectively to mazeration). 4. Light and short antennae (Zoraptera, Thysanoptera) have long and very movable but instable membrane joints. On the other hand the relatively long and heavy antennae (Psocoptera, Aphidina, Psyllina) usually have stable and short membranes allowing less mobility. 5. Sclerotized rings and cylinders, until now not well known, were found to lie within the membrane zones of several Thysanoptera (Thripoidea) as well as Heteroptera (Pentatomidae). If further work confirms these specialized structures to be synapomorphies of the Condylognatha, then we have further proof of the sister-group relationship between Thysanoptera and Hemiptera. 6. A structural mechanism for rupturing antennae is described and analyzed for the first time and is not known to occur in the Insecta. It is built into the flagellar segments. This is the first proof for the monophyletic origin of the Psocodea (Psocoidea): the mechanism exists either in its full functional or partially reduced capacity only in the Psocoptera and Phthiraptera. 7. This structure is characterized by a typically collar-like fold only in the exolayer at the base of the flagellar segments. It functions effectively as a protective device against enemies in the Psocoptera suborders of the Trogio- and Troctomorpha. 8. Lost flagellar segments are not regenerated. An increased elongation of the remaining segments compensates for this, but only in the larvae. The great significance of the antenna] segments for diagnosis is thereby decisively reduced in the Trogio- and Troctomorpha (with respect to the number of antennal segments and annulations; and the length of the segments).

Notes: Summary Different embryonic and postembryonic stages of capsular fluid containing cells of the midgut region in Lymnaea stagnalis L. are described. These cells arise from the archenteron and take up a great quantity of capsular fluid in a large vacuole. At hatching the diameter of the cells mesures 160-200 μ. In opposition to the opinion of Cumin (1972) these store-cells do not transform into cells of the adult midgut; they degenerate in the early postembryonic period. The degeneration starts in a diminuishing of the cell size. Later on autophagic vacuoles can be observed in the cytoplasm, the membrane of the large vacuole breaks up and the nucleus begins to degenerate. Membran bounded granules, which can be observed mainly in early postembryonic stages, are thought to be primary lysosomes. In a last phase the cells seem to be taken up by indifferent cells of the adult midgut.

Notes: Summary The Thomisidae and the Philodromidae are not closely related to each other. The family Philodromidae is the sister group of the Sparassidae (=Heteropodidae), the Thomisidae of the Lycosoidea. The diagnostic characters are listed and evaluated. Aa = autapomorphous character; Pl = plesiomorphous character in regard to all spiders, but the listed characters are considered diagnostic for the two taxa; Sa = synapomorphous characters of the Philodromidae with the Sparassidae; La = synapomorphous characters of the Thomisidae with the Lycosidae.

Notes: Summary The study is concerned with both the functional anatomy of the genital organs and reproductive behavior of the males in the family Erythraeidae. The testes of Erythraeidae consist of a germ layer and a glandular part which produces three different types of protein secretion: Type I forming a thin envelope around sperm cells, type II giving rise to the stalk of the spermatophore, and type III in Abrolophus species secreting a crown topping the sperm drop. Sperm cells and droplets of secretion are floating within a basic fluid in the lumen of the glandular part of the testis. Prior to deposition of the spermatophore, their separation is initiated by a resorption of the basic fluid in the paired vasa deferentia; this in turn causes sperm cells and crown- and stalk secretion to congregate forming uniform complexes. A weir mechanism in the ejaculatory duct is apparently responsible for a final separation. The stalk of the spermatophore is formed in the primary genital opening, whereas the crown is formed in the posterior part of the ejaculatory duct (Camera lamellosa). The secretions of both parts of the spermatophore are hardened by oxidation. Apparently sulphhydrylic groups that are protein-bound join to form bisulfide linkages. An untimely hardening of the secretions-caused by air entering the ejaculatory duct during stalk deposition-is prevented by the oily secretion of an accessory gland (“vordere accessorische Drüse”) which seals the progenital chamber. A thin layer of acid mucus, which stops bisulfide linkages, prevents cementing of the crown in its mold and the hardening of secretions between the hair-like structures of the ejaculatory duct. The sperm drop is formed in the central part of the ejaculatory duct and is covered by a lipid layer produced by a pair of glands (“hintere Lateraldrüsen”). The same lipid serves to both glue the spermatophore to the substratum and glue together the different parts of the spermatophore. During spermatophore deposition the behavior of Erythraeus regalis is similar to that of the Abrolophus species. A deposition is initiated by a circular dance of the male, at which time the female is absent. During the dance a secretion track is set, apparently containing a pheromon. The track seems to ease detection of the spermatophore by the female and permits fast re-detection by the male: In most cases several spermatophores are placed at one location and the oldest one is pushed to the substratum by the male. In the natural biotop, Abrolophus species deposite numerous spermatophores on rocks in the sun within a short time period (in culture jars up to 24 in 2 hrs). During this process, losses of moisture in the genital tract are prevented by the oily secretion of the anterior accessory gland, which fills the progenital chamber. Finally, the homology of male accessory reproductive organs in prostigmatic Trombidiformes is discussed, as well as the phylogenetic aspect of indirect sperm transfer without a previous mating.

Notes: Summary The midgut basal lamina of third instar Oryctes rhinoceros larvae was observed to consist of three structured layers. Each layer contained two structural elements regularly arranged with respect to one another. Type I elements appeared to be morphological variations of closed cylinders with increasing diameters in each layer. The layer of basal lamina closest the midgut epithelium had the smallest, most regular Type I elements. In that layer furthest from the midgut cells the Type I elements were the largest and irregular in shape. Type II elements were morphologically similar in all layers, appearing as dense rod-like elements with a triangular cross section in the plane of the lamina. These elements were interconnected by fine fibrils to form a basic repeating unit: One Type II element surrounded by three Type I elements. Perfect packing of the basic units within the layers of the basal lamina resulted in a pattern of each element type surrounded by three elements of the opposite type. However, variability in the packing of the basic repeating unit frequently occurred. Comparison of the basal lamina of 0. rhinoceros with those of other beetles and fleas previously described showed that this repeating unit occurs in almost all basal laminae containing similar structural units. The basal lamina of 0. rhinoceros, however, appears to be the most complex one yet described.

Notes: Summary Finestructurally the transporting epithelium of the ventral tube in symphypleonan Collembola (Sminthurides aquaticus Bourlet 1842) is characterized by infoldings of the apical and basal plasma membranes and abundant mitochondria. The cuticle above the transporting epithelium possesses the ability to accumulate chloride. The main function of the transporting epithelium in the ventral tube is probably the absorption of ions and water.

Notes: Summary 1. The thoracic skeleton and musculature of the cupedid beetle Priacma serrata Leconte are described and compared with those of Coleoptera hitherto investigated. 2. The prothoracic skeleton is constructed of a pleuron which is visible from outside, and of a quite large, free trochantinus. These features are considered to be primitive. The broadly disjointed coxal articulations and the posteriorly open coxal cavities likewise seem to represent primitive conditions. 3. In the mesothorax the katepisternum can most probably be recognized and its ventral coxal articulation is consistently found. 4. The metathorax is also characterized as very primitive, since a well defined trochantinus, a distinct katepisternum, and the ventral coxal articulations are present. 5. The wing articulation of the mesothorax closely resembles the original configuration. In the mesothorax, basalare, subalare, and a prealar sclerite are present, in the metathorax a second prealar sclerite is also found. 6. The lack of the cervical sclerite as well as the lack of pro- and mesothoracic membranes, and the presence of a sternal process in the prothorax of Priacma may be evidence of derivative tendencies. These features are also found in the Adephaga. It is not possible, however, based on these similarities to confirm a synapomorphic relation between Cupedidae and Adephaga. 7. The prothoracic musculature is more highly, developed than that of other beetles. 8. In the mesothorax a noto-preepisternal, a noto-pleural, and a preepisternal-basalar muscle are described, all of which possess a corresponding muscle in the metathorax. 9. In the metathorax a noto-basalar and a basalar-trochanteral muscle were found, which correspond to muscles in the mesothorax. Also a new mesofurca-metabasalar muscle is described, its corresponding pro-mesothoracal muscle being absent in Priacma. 10. Two basalar-spinasteennl muscles were found, one in the mesothorax, the other in the metathorax. Both spinasterna are present, the sclerotized plate of spinasternum 1 is quite well recognizable. 11. In spite of a few reductions, Priacma shows by far the greatest number of thoracic muscles among known beetles. In particular the muscular equipment of the mesothorax is rather primitive as compared to other beetles. Therefore, the musculature of both pterothoracic segments in the basic plan of beetles should presumably have been rather similar. The mesothoracie and metathoracic musculatures of Priacma are compared in a table. 12. A number of primitive features of Priacma are listed, which should be considered in determining a basic plan for Coleoptera.

Notes: Summary 1. The fine structural architecture of arthropod sensory hairs which had been identified as mechanoreceptive both electrophysiologically and by the presence of a tubular body were examined in serial sections. 2. In addition to the tubular body they are characterized by cuticular elements: a joint membrane, a socket septum and usually by suspension fibers too. 3. In all cases studied at least one of these elements forms the basis for a structural bilateral symmetry along whose plane of symmetry the direction line of the maximum receptor sensitivity lies. 4. The tubular body lies between the hair shaft and the socket septum or an equivalent structure. The hair shaft provides leverage to displace the tubular body and the socket septum (or its equivalent) limits the extent of the tubular body's lateral displacement. 5. The same elements and structural relationships were found in the insertion systems of other arthropod sensory hairs too which were identified by their tubular body but for which no electrophysiological evidence is available.

Notes: Summary The embryonic development ofTarantula marginemaculata can be devided into two phases. Cleavage, germ layer formation, and formation of the body form take place during the protembryonic phase which takes about 20 days and ends with an embryonic moult and rupture of the egg shell. During the following 70 to 80 days (the deutembryonic phase) organogenesis and histogenesis take place, and finally a prenymph emerges from the brood pouch. Cleavage is superficial and ends with yolk contraction. A small germ band is formed by aggregations of cells and a blastopore area appears in its centre. Germ layer formation is achieved by immigration of cells from the blastopore area. The germ band enlarges, and in front of the blastopore area a number of concentric quarter-circular thickenings appear, representing the rudiments of the prosomal segments. At the same time, the cumulus separates from the germ band and migrates towards the future dorsal side. The opisthosomal segments are later formed by proliferation from the caudal lobe. The rudiments of the prosomal segments soon become more distinct and narrower. Later, each is devided into two halves which, during reversion, separate and migrate to lateral positions. Reversion is similar to that of mygalomorph and haplogyn spiders. The cumulus migrates along the dorsal midline nearly towards the front end of the embryo and finally desintegrates by forming yolk cells which participate in the formation of the anterior mid gut rudiment. Seven pairs of coelomic cavities are formed within the prosoma and 12 within the opisthosoma. The formation of dorsal and ventral diaphragma, heart, endosternite, musculatur etc. is described and the significance of the ventral diaphragma and endosternite is discussed. The first pair of coelomic cavities, the precheliceral coelom, underlies the head lobes and later supplies the labrum (rostrum) and stomodaeum and forms the aorta anterior and the arteriae crassae. This coelom is most likely homologous to the preantennulary coelom of many mandibulates. It is the only indication of a precheliceral segment which has been lost or fused with the acron. The most conspicuous characters of the amblypygid brain are huge globuli-cell masses covering the entire brain, and glomeruli in the first leg ganglia. A well developed stomodeal bridge is present, giving rise to an unpaired rostral nerve and perhaps paired lateral nerves also. Development of the central nervous system involves many small invaginations. The brain is formed from the large precheliceral lead lobes which are later devided into the median part and lateral vesicles. Most of the brain, including central body, corpora pedunculata, and median optic masses, are formed by the median part of the head lobes. The lateral vesicles give rise to the optic masses of the lateral eyes and part of the optic centre. These and other structures can hardly be regarded as precheliceral segmental neuromeres. The lateral vesicles may be homologous to the optic lobes of the Mandibulata. The neuromeres of hypothetical precheliceral segments (prosocephalon, deutocephalon) have either been completely lost or completely fused to the archicerebrum, or the prosocerebrum is represented by the rostral ganglia.

Notes: Summary 1. There are three connective chordotonal organs associated with the sound producing apparatus of cicadas: a) the tymbal chordotonal organ, connected to the lower anterior margin of the tymbal; b) the tensor chordotonal organ, connected to the special protuberance bearing the origin of the tensor muscle; c) the detensor chordotonal organ, connected to the cuticle near the inner margin of the tympanum, beneath the detensor tympani muscle. 2. A newly described muscle, the accessory tensor muscle, originates next to the proximal attachment of the tymbal organ and inserts alongside the insertion of the tensor muscle. 3. These chordotonal organs contain an exceptionally large number of sensillae: tymbal organ, 650–1300 scolopidia; tensor organ, 200–350 scolopidia; detensor organ, 325–400 scolopidia. 4. Each scolopidium consists of the following cells: a bipolar neuron with dendrite bearing a sensory cilium, a scolopale cell, a proximal attachment cell, a distal attachment cell. Scattered Schwann cells surround the sensory axons. 5. The scolopale has the usual fine structure but the following features are distinctive: a) the scolopale is composed of a continuous tube of scolopale material, not separate scolopale rods; b) the scolopale material varies markedly in thickness in different regions of the scolopale; c) the extracellular cap, which anchors the cilium distally, is very small and is entirely surrounded by the scolopale. 6. From the morphological evidence, it is suggested that these chordotonal organs provide a very sensitive monitoring system for the activity of the sound producing apparatus.

Notes: Summary The very special head structure of Desmotimmia mirabilis (Timm, 1961) Freudenhammer, 1975, differs from all other nematodes in showing a hexaradial symmetrical labial region with 6 lips around a hexagonal mouth and bearing but one circlet of only four labial setae: 2 lateral ones, the right subdorsal and the left subventral. The head of D. mirabilis, not clearly defined until now, is composed of 3 consecutively broader rings, each consisting of an anterior non-sclerotized and a posterior sclerotized part, and separated by a narrow interzone from the broader concretized first body ring.

Notes: Summary 1. The peripheral tympanal region of the Tettigonioidea (long-horned grasshoppers) has been investigated by means of the scanning electron microscope. 2. The tympana are composed of two membranous parts having different structure. There is an outer, ellipsoid region with a honeycomb structure comparable to that of the surface of the forelimb exoskeleton; around this lies a thin crescent-shaped membrane with a fibrillar texture. The latter part is probably relatively elastic and capable of oscillation. 3. The actual site of the auditory receptors in these grasshoppers, the crista acoustica, takes the form of a row of scolopidia; the sizes of the scolopidia decrease progressively from proximal to distal. The cap cells of the scolopidia are covered by the tectorial membrane; in the middle and distal region of this membrane there are supporting bands running lateral to the cap cells.

Notes: Summary The mesenchyme of Ephydatia fluviatilis is “open” toward the incurrent canal system. All the cells of this fresh water sponge show contractile vacuoles and are capable for an active osmoregulation.

Notes: Summary The identity of the fluid pressure pumps in spiders was investigated in Filistata hibernalis through measurements of the activity of certain muscle groups, leg movements, and changes in fluid pressure within the leg. Our results indicate the cephalothorax is the site of the pressure pump responsible for leg extension and the musculi laterales are the major muscles involved in the operation of this pump. Fluid pressures in the legs averaged 5 100 N·m−2 in resting spiders, ranged from 4 000 to 6 700 N·m−2 in walking spiders and reached as high as 61000 N·m−2 in startled spiders. Intra-abdominal fluid pressures were also measured and found to be much lower, ranging from 1000 to 4 000 N· m-2. These pressures are the result of activity of at least two sets of abdominal muscles, the sub-cuticular muscle sheet and the paired series of dorso-ventral muscles. We suggest the abdominal fluid pressure and the rigidity of the book-lungs attenuate pooling of the hemolymph in the abdomen when the spider is active. Finally we hypothesize that evolution of the hydrostatic skeleton in spiders has allowed a greater mass of flexor muscles to be incorporated into the legs and this in turn is an adaptation to the spider in prey capture.

Notes: Summary The fine structure of various tubular appendages of the abdomen of aquatic Nematocera larvae was comparatively studied in representatives of 9 families with respect to their possible functions. These appendages are 1. the anal papillae which occur in all aquatic Nematocera larvae, 2. the abdominal tubules of red Chironomus larvae, and 3. the tracheal gills of Liponeura. The anal papillae of all species studied possess typical transporting epithelia and, therefore, exert an osmoregulatory function as known for larval Culicidae. The presence of tracheoles in the papillar epithelium of some species suggest that they may be additionally involved in respiration comparable to the unspecialized integumental-tracheal respiration. No structural indications were observed which justify the former designations of the anal papillae as tracheal gills or blood gills. The 5 paired tufts of tubules on the ventral side of Liponeura are densely equipped with tracheoles. Their fine structure is typical of tracheal gills and suggests that they are exclusively respiratory in function. The abdominal tubules of red Chironomus larvae have very thin epithelia. In one of the species studied the epithelium is only 0.1 to 0.2 μm thick and resembles the respiratory epithelia of vertebrate lungs and gills, suggesting that these tubules serve as blood gills. In the second species studied the epithelium measures ca. 1 μ in thickness. The presence of short microvilli, infoldings of the basal plasma membrane and small mitochondria indicates that, to a small extent and depending on the species, the abdominal tubules are also capable of active transport.

Notes: Summary Tyloses form in red oak (Quercus rubra L.) sapwood in a period of hours if the wood is cut during the active growth season and stored in green condition in the laboratory. If the wood is cut during dormancy and stored in green condition, tyloses form in a period of months. Electron microscopic examination reveals that the wall of a tylosis forms from a promonths. Electron microscopic examination reveals that the wall of a tylosis forms from a protective layer that develops inside the secondary wall of the ray cell in the vessel-ray pit-pair. Protective layers are also present in fiber-parenchyma pit-pairs. Protective layers may exhibit variable thicknesses, with light and dark layers alternating. A young tylosis wall consists of two layers: An electron-dense outer layer and an electron-transparent inner layer. Tyloses walls may attach to each other and form multilamellate tyloses. Sometimes the individual layers of tyloses walls appear lamellated. Because of the type of formation and structure, the tylosis wall in red oak apparently is a primary wall rather than a secondary. Tyloses walls have simple pits. The findings of this study enable felled hardwoods with potential for forming tyloses to be used without the destructive influence of tyloses.

Notes: Summary Ultraviolet absorption spectra were determined microscopically for the different morphological regions of fourteen hardwood species. The woods were chosen to represent a range of methoxyl to carbon nine ratio (MeO/C9) in their lignins. The various trends in absorbance and peak wavelength indicated that 1. Syringyl residues become increasingly predominant in the walls of the fiberes and ray cells as the MeO/C9 ratio of the lignin increases. 2. The vessel walls and cell corner regions contain mostly guaiacyl residues except at high MeO/C9 ratios when the syringyl character of the vessel walls increases. If certain reasonable assumptions were made, it was possible to resolve the spectrum of the fibre wall of eastern cottonwood into spectra of the syringyl, guaiacyl and p-hydroxy benzoic acid components.

Notes: Summary Tension members with edge knots or edge knotholes deflect laterally when they are loaded by a tensile force. In order to consider this behavior for determination of tensile strength ratio (TSR), second-order theory is applied. A matrix displacement method of structural analysis developed from the slope deflection method is used to implement the second-order theory. The method reveals that in a member with a single edge knot the lowest TSR is obtained when the lateral deflection is negligible, and when the ends are hinged. For a stiffness value (EI/L) that is small, both end conditions (hinged and fixed) yield the same TSR; for large stiffness value, fixed end condition always gives a higher TSR than a hinged end condition because the moment is reduced at the defect as a result of the fixed ends. The method further reveals that the maximum moment for two edge knots on the same edge is lower than when they are on opposite edges. The findings are important because they can provide guidance in planning tensile testing methods for lumber, in interpretation of results of tests, and in design considerations. These findings help to develop better relationships between TSR, which is an index of tensile strength (T), and apparent modulus of elasticity, Ea, which are so important for the determination of the best predictor of T.

Notes: Summary Wood samples varying in age from 900 to 4400 years were investigated with the electron microscopes (TEM, SEM) and polarized light microscopy as well as by analysis of the mechanism of fracture. The weakest parts of the structure, and therefore the most susceptible to failure, are the middle lamella/S1 region and the interfibrillar matrix. Parts of the wall exhibit fissures, cracks and loss of adhesion, not found in recent wood. Studies of the fractured surfaces confirm a change in the micromorphology of the old wood samples. In spite of the breakdown of certain elements at ultrastructural level the samples had retained almost their normal macroscopic appearance and properties. As long as the main reinforcing structural elements, the microfibrils, remain intact, the major properties of wood do not apparently undergo drastic changes.

Notes: Summary Veneers treated with subtoxic levels of a copper containing wood preservative were inoculated with various fungi and soil and incubated in the laboratory in such a way that hyphae could grow away from the wood. Afterwards any copper moved out of the wood was measured. Every culture tested formed mycelium which moved some copper, and species known to be copper tolerant gave the greatest movement of the metal away from the wood. The amounts invariably increased with time and no distinct adaptation to the toxicant, involving a lag phase before copper movement occurred, could be discerned. Copper was distributed evenly wherever hyphae grew. The amounts varied with different temperatures, pH's and preservative concentration and reflected the growth response of the cultures to these parameters. The monocultures did not considerably move more copper from one kind of wood, though the soil fungi were always most active on Scots pine. The copper which was moved appeared to be that not fixed in the wood. Generally the results indicated that the movement of copper was by a translocation mechanism linked to fungal growth.

Notes: Summary A new method is presented for measuring fractional cell wall area by use of photomicrographs of cross sections of wood. The method is geometric in approach and measures, within a delineated area of complete cells, compound cell wall thickness of adjoining cells in systematically or randomly selected locations. In comparison to point sampling (dot grid method), applied with single or repeated trials, the proposed method is shown to require a lesser number of samples for the same statistical accuracy. In addition to fractional cell wall area, the method serves to determine mean cell and lumen area (or diameter).

Notes: Summary The development and localization of phenolic compounds in sapwood and heartwood of Abies alba Mill. have been studied using cytological and UV-microspectrophotometric methods. The synthesis of phenolic substances was apparently initiated in vesicles developing from rough ER of the ray parenchyma cells in sapwood. They are different from the phenolic material in the pit membrane and cell wall of heartwood. There was no indication to suggest that the polyphenols in the cell wall of heartwood were either derived from or identical with the phenolic substances in the lumina of ray cells.

Notes: Summary Samples of different wood species varying in age from 900 to 4400 years and stored during this period under different conditions were analyzed for their lignin content. Lignins isolated from the samples were investigated by IR-spectroscopy. It could be shown that lignin in wood undergoes oxidative changes which lead to a decrease in the amount of lignin isolated by the hydrochloric acid procedure. at Hamburg-Lohbrügge.

Notes: Abstract A quantitative study was made of the strain field near the knife and nosebar in a slow linear veneer cutting. A grid of 0.01 in. mesh was printed on the side of the specimen, and measurements on photographs taken before and during cutting were used to calculate strains. Nosebar type (single-faced, double-faced and roller), nosebar gap, and nosebar lubrication were varied. The work-pieces were of regrowth redwood (Sequoia sempervirens Endl.) and plantationgrown douglas fir (Pseudotsuga menziesii (Mirb.) Franco). A “maximum principle strain” criterion appeared to accord with rupture formation. The single-faced nosebar was more effective in reducing maximum principle strain at the knife edge, but produced greater values of that parameter at the nosebar edge, while the roller nosebar had reverse effects. Lubrication with silicone grease had only small, generally favourable effects. Uneven texture of the work-pieces increased variability of results, but provided some insight into control of peeling checks, compression tearing and nosebar tear in cutting veneer from difficult species.

Notes: Summary The development of bordered pit sites in the cambium of Pinus radiata D. Don was studied using light and electron microscopy. No primary pit fields occur in the fusiform initials and no plasmodesmatal connections were seen in radial walls of undifferentiated cambial cells or differentiating tracheids. Thin areas bounded by a thick rim appear in the radial walls of these cells once enlargement is under way. They appear to result from a redistribution of wall material which, it is suggested, is brought about by some agent which penetrates the primary wall. The thin areas, which are the sites of bordered pits, are common to the cells joined by the affected wall, and the rim which protrudes symmetrically into each cell provides a template on which the border is subsequently formed. This mechanism would explain how symmetrical pit pairs can be formed in the absence of plasmodesmata.

Notes: Abstract The pyrolysis of native jack pine bark has been studied from 200 to 340°C by thermogravimetric (TG), and isothermal weight-loss methods. The effects of particle size, solvent extraction and additions of zinc (II) and iron (III) chlorides on the pyrolysis behaviour have also been examined. The bark was characterized by infrared spectroscopy and low-temperature gas adsorption. Residues were analysed for CHN contents and structural changes which occurred on heating were examined by optical and scanning electron microscopy. The TG characteristics were not affected by solvent extraction or particle size variation while the metal chloride additions inhibited the loss of volatile materials from the bark probably by stabilizing chemical bonding in the bark components. Isothermal decomposition data were found to fit established kinetic expressions associated with inorganic decompositions. The physical mechanics of pyrolysis have been interpreted on the assumption that pyrolysis is initiated through the formation of planes of lateral strain which are sites for decomposition and which decrease in number inversely with time. It is suggested that these sites are produced by an oxidation mechanism which may be rate-controlling in the pyrolysis. This hypothesis is supported by the observation that the data fit a reaction rate compensation curve, often associated with oxidation processes but more generally with heterogeneous catalytic reactions. The compensation curve also relates the kinetic parameters found by other workers for a large variety of wood-derived materials.

Notes: Abstract Observations were made on the brooding behavior of 10 laboratory reared female Octopus joubini, including egg laying, care of the eggs, feeding during brooding, and survival of the female from the onset of egg laying. Data concerning the numbers of eggs laid by each female and hatching (duration, frequency, correlation of duration to water temperature, etc.) are given. The newly hatched octopuses (whose ages were determined within 24 h) were fed Uca spp. to determine their growth rate from hatching to 4 months of age. In addition, some specimens were presented with a variety of foods that were easily accessible in the laboratory or field in an effort to find a food suitable for mass culture.

Notes: Abstract The site of reef-coral calcification has been studied in the branching coral Pocillopora damicornis Lamarck. Electron microscopy and X-ray microprobe analysis were performed on the calicoblast epidermis of newly settled larval stages and of adult coral. During settling, the heterogeneous columnar cell composition of the planktonic larva epidermis is replaced by a simple epithelium consisting of a single cell type, the calicoblast cell. Metamorphosis appears tightly linked to settling, with cell changes occurring within hours after attachment, and is marked by the appearance of a new secretory cell. The calicoblast cell of the adult coral is extremely flattened, and interdigitates extensively with adjacent calicoblast cells. This cell possesses a featureless plasma membrane lacking microvilli or flagella. It characteristically contains large membrane-bound vesicles with homogeneously fine granular contents. Preliminary microprobe analysis indicated a higher calcium content in these vesicles than in surrounding tissue; however, not in concentrations suggesting calcium-carbonate precipitation. They may represent sites of organic matrix synthesis. The calicoblast epidermis is separated from the underlying coral skeleton by a narrow gap. This gap appeared devoid of substructure, either organic or inorganic. The coral soft tissues are attached to the skeleton by mesogleal attachment processes, the desmoidal processes. These consist of a complex fibrous network originating in the mesoglea, and inserting onto the skeleton via specialized attachment regions consisting of electron-opaque membranous plaques. Skeletogenesis in reef-corals probably occurs extra-cellularly, external to the calicoblast epidermis, by simple overgrowth of the skeleton.

Notes: Abstract Experiments were made on decomposition of dissolved organic matter (DOM) in coastal seawater (Sagami Bay and Tokyo Bay, Japan). Decomposition of DOM seems to proceed in two steps: a rapid decrease in DOM during the first several days, followed by a slow decrease after this time. The apparent rate constant for decomposition of the total DOM was calculated as 0.01 to 0.09 day-1 for the first step and 0.001 to 0.009 day-1 for the second step, assuming that such decomposition proceeds as a first-order reaction. A part of such utilizable fractions of DOM may be derived from excretion and decomposition products of phytoplankton, especially “red-tide” organisms occurring in summer. Molecular weight distribution of DOM changed with advancing decomposition. The low-molecular-weight DOM (mainly less than 500) in the surface water of Tokyo Bay was 0.67 mgC/l (24% of the total DOM) at the initiation of incubation; this decreased to 0.36 mgC/l (16% of the total DOM) after 2 days incubation at 20°C in the dark. Low-molecular-weight DOM was thought to be firstly utilized by micro-organisms. After 6 to 10 months incubation, the proportion of low-molecular-weight DOM decreased and that of high-molecular-weight DOM increased.

Notes: Abstract This paper considers the adaptive significance of two different reproductive methods in two co-occurring, competing sea stars. The smaller (3 to 8 g mean wet weight) Leptasterias hexactis broods relatively few, large young in the winter, while the large (300 to 650 g mean wet weight) Pisaster ochraceus broadcasts relatively many, small eggs each spring. L. hexactis matures at a small size (2 g wet weight) in about 2 years, and P. ochraceus matures at a larger size (70 to 90 g wet weight) in about 5 years (Menge, 1974). As in many broadcasting asteroids, gonad and storage organ indices of P. ochraceus are inversely related over time, and maximum storage-organ index correlates with the summer feeding maximum (Mauzey, 1966). In contrast, both organ indices of L. hexactis and feeding increase and are positively correlated until early autumn, when feeding activity begins to decline. At this time the male gonad index continues to rise, and the storage-organ index drops. In contrast, both organ indices of females rise. Spawning occurs from November to January. Thereafter storage-organ indices decline in females, presumably because females draw upon energy reserves while brooding; storage-organ indices rise in males, presumably because males do not brood and can feed if food is available. The primary cause for the differences between annual reproductive cycles of P. ochraceus and L. hexactis is suggested to be patterns of food availability for the released young (planktonic food for the broadcasted young of P. ochraceus and benthic prey for the brooded young of L. hexactis. Estimates of pre-maturity survival and post-maturity longevity indicate that the probability of survival per individual of young P. ochraceus is vastly lower than that of L. hexactis. However, once mature, P. ochraceus has a much longer expected lifespan. Brooding is suggested to be a coadaptive consequence of competition-induced small size. Assuming planktonic mortality rates in this environment are roughly constant across broadcasting species, I suggest that a small broadcasting species could not produce enough offspring in its expected lifespan to replace itself. This hypothesis is partly supported by some simple simulations. Broadcasting is suggested to permit rapid location and utilization of spatially and temporally unpredictable, but highly desirable, resources by allowing rapid and widespread dispersal. Brooders presumably cannot disperse rapidly and must rely on more reliable, but perhaps less desirable, resources. Factors affecting reproductive patterns in marine invertebrates include (1) food availability for both adults and offspring, (2) planktonic mortality rates, (3) interactions between species and latitudinal changes in these factors, and (4) various physical factors. This paper suggests that competition and predation can have an important effect on the evolution of reproductive methods, a possibility heretofore largely ignored. Although several similar examples of co-occurring species' pairs which differ in reproductive method and size are available, the role of adult interactions is unknown in these examples.

Notes: Abstract Data on abundance, biomass and biovolume demonstrate the significant ecological role of oligochaetes in the littoral marine benthos. Their numerical and productive importance is comparable to that of many other common meio-and macrofauna groups from various littoral areas. Oligochaetes often exhibit nutritional specialization (e.g. bacteria or diatoms attached to detritus or sand grains). Consequently, food supply can control their population structure and distribution. Few oligochaetes are, apparently, consumed by predators. Hence, only a small portion of their biomass is transferred to higher trophic levels, while the main part is decomposed directly. Most oligochaetes seem to represent final links of rather short food chains. Ecologically, marine oligochaetes attain major importance only in littoral areas.

Notes: Abstract In 1974, spawning polychaetes, Anaitides mucosa (Oersted, 1843), appeared in great numbers (up to 148 individuals/m2) at the surface of an intertidal flat in the German Waddensea from mid-February until 10th April. A. mucosa forms mucous bags which usually contain more than 10,000 green eggs. The eggs measure 113.4±5.4 μm in diameter, including the fructification membrane (18 measurements). Production if these egg bags was observed 5 times in nature and 4 times in the laboratory. Four to 17 males and 1 female form a ball of interlacing bodies. At the same time a mucous mass is secreted by the female — maybe also by the males — which increases to a diameter of as much as 2 cm within about 8 min. Eggs and sperm are shed into this mass of mucus. The worms appeared at the surface of the flat from early sunset until sunrise from about 3 h before to 1 h after low tide. Judging from observations of worms in the laboratory, it seems possible that the rhythm of sexual activity is controlled endogenously.

Notes: Abstract At higher latitudes along the west coast of the USA the herbivorous intertidal snail Tegula funebralis (Adams, 1854) lives longer, grows more slowly, but attains a larger size than further south. To the north, age distributions are less predictable and often far from stationary. The differences, which have some generality, can be explained either by a primary temperature effect joined with increased hazards to planktonic larvae in the north, or else may result from a combination of interactions between intensity of predation, population density and food supply. Growth rates of transplanted individuals suggest a genetic basis for the latitudinal differences.

Notes: Abstract Groups of male Uca pugilator (Bosc) (Crustacea, Decapoda, Ocypodidae), acclimated to sublethal pressure (34 atm) subaqueously for 5 and 10 days, were observed subsequently at pressures up to 272 atm. Behavioral indicators of pressure resistance (“first response” and tetany) were employed to measure degrees of pressure acclimation in comparison with simultaneously and non-simultaneously conducted control experiments. No firm conclusions can be made on the basis of “first response” results, but the pressures required to induce tetany were significantly higher (P≤0.02, one-tailed comparison) in acclimated groups than in non-acclimated groups. These data and earlier studies by other investigators support the assertion that some shallow marine species are capable of at least limited short-term pressure acclimation.

Notes: Abstract The marine phytoplankter Dunaliella peircei was exposed to a concentration of 10.00μg/l of the chlorinated hydrocarbon insecticide dieldrin in sea-water solution. After 24 h exposure, the dieldrin residue level in the alga was 12.10μg/g, corresponding to a magnification factor of 1210. Clams, Rangia cuneata, allowed to feed on dieldrin-contaminated phytoplankters for 48 h exhibited a magnification of dieldrin residues in tissues up to 54 times greater than the concentration resulting from the resuspension of contaminated algal cells in clean seawater. This study demonstrates the transfer of dieldrin residues in a two-level food chain, i.e., from a contaminated alga to a bivalved mollusc allowed to feed on this alga.

Notes: Abstract The production of algae in the Patuxent River estuary (Maryland, USA) was much less than the carbon requirements of a population of the calanoid copepod Eurytemora affinis. Detrital carbon was present in quantities that suggest turnover times of 8 to 83 days for this pool, assuming that all algal production was consumed by E. affinis. We hypothesize that E. affinis must consume detritus to meet a part of its requirements for energy.

Notes: Abstract The influence of zinc upon the pattern and success of settlement was examined in the oyster Crassostrea gigas. Late larvae were more tolerant of zinc than embryos. A delay in settlement was recorded in treatments containing zinc as low as 125 μg/l, and numbers of larvae settling was reduced in the presence of zinc. Larvae subjected to zinc immediately prior to settlement showed evidence of slowing in behavioural development. Those larvae which settled in the presence of zinc, however, when ongrown in clean water were as viable as controls. Zinc at concentrations of 250 and 500 μg/l suppressed spat growth, but recovery was rapid upon subsequent on-growing in clean water conditions.

Notes: Abstract Photosynthetic assimilation of 14CO2 by the symbiotic green alga Platymonas convolutae Parke et Manton in the marine flatworm Convoluta roscoffensis Graff has been investigated and compared with that in free-living P. subcordiformis and P. tetrathele. All Platymonas species investigated rapidly incorporate 14CO2 into a complex variety of soluble and insoluble assimilates. The rate of dark fixation is considerably lower in P. convolutae. Typical 14C-assimilate patterns are rather uniform in all Platymonas species, but the time courses of 14C-labelling of several compounds are very different. The percentage of 14C-aspartate and 14C-malate is significantly higher in P. convolutae after short-term-photosynthesis, whereas 14C-labelled phosphate esters predominate in the free-living Platymonas species. A comparison of the kinetics of 14C-labelling and of the distribution of 14C-activity between soluble and insoluble fractions suggests that glucose and fructose, not mannitol, as well as several amino acids (especially alanine) move from the algal partner to the tissue of the animal host. The significance of these findings is discussed.

Notes: Abstract The distribution of coccolithophores was studied in the neritic environment along the western margin of the Pacific Ocean: the Inland Sea of Seto, Yellow Sea, East China Sea, South China Sea, Java Sea, Timor Sea, Arafura Sea and Gulf of Carpentaria. The coccolithophore community in the Red Sea was also studied for comparison with the Pacific marginal seas. With minor exceptions, the coccolithophore communities were very similar throughout the neritic areas investigated, but differed completely from the pelagic community in three aspects. Firstly, almost all neritic coccolithophores, regardless of species, suffered various degrees and forms of malformation with relation to the morphology of their coccoliths, while such malformation was rare in the pelagic population. Nitrogen deficiency may cause such malformation. Secondly, the diversity of species in these marginal seas was much lower than in the pelagic environment, although no species was found to be exclusively neritic. Emiliania huxleyi, usually ubiquitous in oceanic areas and in various neritic environments of higher latitudes, was scarce, while Gephyrocapsa oceanica dominated the flora throughout the studied areas. Finally, the horizontal and vertical distributions of the neritic populations were sporadic compared to those of the rather uniform pelagic environments.

Notes: Abstract Rhodophysema georgii Batt., a rare epiphyte on Zostera spp., was collected from lowtide-level lagoons at Bembridge (Isle of Wight), and its life history examined in laboratory culture. The tetraspores, the only method of reproduction known, gave rise to small crusts which again developed tetrasporangial sori on the surface, similar to those of the parental material. It is suggested that this “direct” type of life history is probably due to the repression of meiosis in the tetrasporangial mother cell.

Notes: Abstract Experiments on 4 phylogenetically different phytoplankton exposed in culture to a range of concentrations of benzene, toluene and xylene showed a variety of growth responses for marine microalgae. The degree of influence of these aromatic hydrocarbons, all components of fuel oils and crude oils, varied with concentration, compound and species. Stimulation of growth in Dunaliella tertiolecta resulted from low μg/l concentrations of all three compounds, Skeletonema costatum showed no growth enhancement, while Cricosphaera carterae and Amphidinium carterae were intermediate in their reactions. Closed culture vessels were found to be necessary to retain these volatile hydrocarbons. Many of the previous laboratory studies on oil using standard methods — cotton plugs, screw caps or beakers — have overlooked the important influence of the volatile fraction. The species-specific stimulation of low concentrations was further shown in experiments with mixtures of No. 2 fuel oil. The volatile fraction was most biologically reactive, being the source of growth enhancement at low levels and a major growth inhibitor at high concentrations. Thus, a significant environmental effect of oil on marine primary production could be the growth stimulation of particular species by low molecular weight aromatic compounds resulting in an alteration of the natural phytoplankton community structure and its trophic relationships.

Notes: Abstract Oysters (Crassostrea virginica) were exposed for 3 days to mercury-203 labeled HgCl2 or CH3HgCl added directly to artificial seawater or added preconcentrated on the marine diatom Phaeodactylum tricornutum. The concentration of mercury in 5 tissues was measured for 45 days after mercury was removed from the ambient water. At the beginning of the depuration period, the highest concentrations of mercury in tissues were attained in: gill〉digestive system〉mantle〉gonad〉muscle in oysters exposed to water containing mercury; and in digestive system〉gill〉mantle〉 gonad〉muscle in oysters fed labeled algae. This same distribution pattern is seen for both chemical forms of mercury. Although the initial pattern of accumulation was identical for both mercury compounds within each exposure group, the fate of the accumulated mercury was very different after 45-days depuration. In oysters accumulating mercury directly from seawater, inorganic mercury residues rapidly declined in gill and digestive tissue, but were slowly reduced in mantle, gonadal, and muscle tissue. This pattern was duplicated by oysters exposed to methyl mercuric chloride in seawater except that gonadal and muscle residues greatly increased during depuration. In oysters ingesting labeled P. tricornutum cells, mercuric chloride and methyl mercuric chloride residues rapidly declined in gill and digestive tissue, remained constant in the mantle, but sharply increased in gonadal and muscle tissue during depuration.

Notes: Abstract The lateral or along-shore distribution of the polychaetous annelids of a subtropical, sandy, intertidal habitat in Florida (USA) was studied on three transects (covering 2.5 km of shoreline), sampled quarterly for 2 years. Although the average species number and density of individuals were not significantly different at specific tidal levels, the species composition was highly variable over time. Composition of density dominants was identical along-shore, and down-shore density distribution of selected species was also identical. Analysis by entire transects rather than by individual stations decreased along-shore heterogeneity by 10 to 15%.

Notes: Abstract Some aspects of the maturation and spawning of the commercially important prawns of the Arabian Gulf, Penaeus semisulcatus de Haan, Metapenaeus stebbingi Nobili and Trachypenaeus granulosus (Haswell), have been studied. Five maturity stages: immature, early maturing, late maturing, mature, and spent-recovering, are distinguished, and the maturation process in the female of each species is described. The minimum size at first maturity was estimated to be 126 mm for P. semisulcatus, 88 mm for M. stebbingi and 64 mm for T. granulosus. T. granulosus breeds throughout the year, with peaks in June, November-December, and in April; in P. semisulcatus and M. stebbingi the breeding period extends over the period October to March or April.

Notes: Abstract During the second cruise of the R.V. “Professor Siedlecki” in spring and summer, 1973, concentrations of anchovy and hake were reported in the area off Golfo Nuevo and the Bay of San Mathias, Argentina. Observations were mainly made with the help of acoustic equipment. The echo recordings revealed an interrelationship between the presence of anchovy schools and the appearance of hake concentrations. This paper demonstrates that this relation is trophic in character.

Notes: Abstract Following a lag of 3 to 18 h, acetylene reduction in mannitol-amended sand systems proceeded at approximately constant and high rates for periods up to 4 days. Carbon dioxide production and O2 consumption were low in these systems in comparison to similar systems additionally amended with ammonium, indicating N-limitation of growth in the former. Thus, long-term acetylene assays of mannitol-amended sand and suspensions from the sand incubated at various partial pressures of oxygen could be used to characterize the O2-sensitivity of the N2-fixing bacterial population as a whole, in batch-type systems with a minimal degree of enrichment or change in pO2 during the course of the assays. Results of various studies suggested that aerobic or microaerophilic N2-fixing bacteria were absent or scarce in the sand, and that nitrogenase activity occurring in aerobically incubated systems occurred in anaerobic microenvironments. Hydrogen stimulated acetylene-reducing activity, but the time course differed from that of mannitol-supported activity, and proceeded with shorter lags in systems incubated at 0.2 and 0.05 atm O2 than in systems incubated anaerobically. Efficiency of N2 fixation [C2H2] increased with decreasing initial mannitol concentration. For sand washed with seawater to remove native combined inorganic nitrogen, and amended with 0.015% mannitol, 374 μmoles added NH4-N/kg wet sand caused almost complete repression of nitrogenase activity, while concentrations as low as 12 μmoles added NH4-N/kg wet sand appeared to cause at least partial repression of nitrogenase activity. Some implications of these results for the existence of anaerobic microenvironments in the cavities of skeletal carbonates, and for N2-fixation in the seagrass rhizosphere are discussed.

Notes: Abstract Field studies of whole natural phytoplankton communities from Knight Inlet, B. C., Canada and laboratory cultures of the diatom Skeletonema costatum indicate inorganic carbon fixation may be temporarily suppressed following 10 to 15% enrichment with NO 3 - or NH 4 + . (This effect is suggested to be due to competition between inorganic carbon and nitrogen for adenosine triphosphate (ATP), and is reduced when chlorophyll a is increased intracellularly after 6 to 8 h.) Results imply that the source of ATP for nitrate uptake is primarily from Photosystem I (cyclic photophosphorylation) in the presence of light. It would appear that a transient nutrient-adaptive response occurs upon addition of extracellular nitrogen.

Notes: Abstract The prototype Undulating Oceanographic Recorder Mark I is an instrumented towed vehicle which can be programmed to undulate between a minimum depth of 8 m and a selected maximum depth between 15 and 70 m, with an undulation length between 3 and 30 km, at any speed between 7 and 15 knots (3.6 to 7.7 m/sec). It takes a continuous series of plankton samples, each integrated over the undulation depth range, and records data on magnetic tape, at a preselected rate between 30/min and 30/h, from which salinity, temperature and depth can be derived with accuracies of ±0.1‰, ±0.1C° and ±0.5 m, respectively. The instrument is automatic, self-contained and generates its own power supplies. It is towed on about 200 m of unfaired steel cable and can be handled with the winching and lifting equipment found on most research vessels. Examples of processed data from three cruises are presented: temperature and salinity contours on a vertical section through a complex stratified area in the N.W. Irish Sea; results from a survey of the waters over the continental shelf and slope to the north of Scotland, showing the distribution of water masses and associated plankton; and hydrographic data taken in Loch Etive on the west coast of Scotland.

Notes: Abstract Populations of the crab Scylla serrata (Forskal) were studied in two South African estuaries from 1971 until 1974. One estuary was open to the sea, the other was closed by a sandbar. Population density in the closed estuary was estimated by means of mark-release-recapture data from tagged crabs. The population of S. serrata was estimated as 1 crab/124m2 and the production at 3.4 g/m2/annum. Catch per unit effort data from the closed estuary indicated a natural mortality of 41% in the crabs' second year and 60% in the third. Growth was studied in both estuaries by means of size-frequency analysis and from tagging returns. Growth was rapid in the first 12 to 15 months, when the crabs attained a carapace width of 80 to 160 mm. Thereafter growth slowed, and after 3 years crabs were between 140 and 180 mm in carapace width. Females mated in summer at a carapace width of 103 to 148 mm, males at 141 to 166 mm. After mating, females migrated out of both estuaries into the sea.

Notes: Abstract Observations on the effects of several environmental conditions in embryonic and larval cultures are reported for the gooseneck barnacle Pollicipes polymerus (Sowerby, 1833). When the growth rates of control embryos kept in finger bowls at ambient-temperature sea water (ca. 12°–15°C) were compared to those of embryos grown under variously modified circumstances, it was found that growth rates were faster under conditions closely simulating the adult barnacle mantle-cavity (e.g. darkness and aeration). Addition of antimicrobial drugs and reduction of egg-mass size also promoted fast growth and development. Nauplii were fed several species of algae; only three species promoted growth to Stage V or older. Naupliar growth was fastest in larvae fed the combination of Prorocentrum micans/Platymonas sp. Larvae fed Prococentrum micans/pennate diatom grew slowest, and most larvae died at Naupliar Stage III. Interactions between algal species may have affected their nutritional value for Pollicipes polymerus nauplii. Less larval activity, slower growth rates, and higher mortality rates were observed in individuals given small amounts of food. The development of embryos and larvae in culture depends greatly on the culture conditions. These conditions should be described if comparison of timetables and envents are to be made between studies.

Notes: Abstract Macoma nasuta Conrad is primarily a deposit-feeding bivalve sucking the top millimeter of the sediment surface. Growth experiments show that surface sediment supports growth better than detritus falling from the water column. Gut clearance time is between 1 and 9 h (12°C). Fecal pellets are ejected in a regular rhythm. However, the total amount of feces per unit time shows considerable individual variation. Due to sorting in the mantle cavity, about 97% (dry weight) of the surface material is ejected again as pseudofeces. Selectivity by the bivalve is estimated by comparison of particle size and organic composition of sandy and muddy sediments and compared with feces produced by clams fed these sediments. Fecal pellets are in all cases richer in organic components than the sediment, indicating a high degree of selectivity. Ingestion and digestion of small animals (meiofauna) occur, but many of the ingested specimens survive. It is not possible to estimate the assimilation of organic matter by simple difference between the ingested sediment and the ejected feces. The difficulties in calculating energy budgets which arise from selective feeding and associated bacteria are discussed.

Notes: Abstract The importance of desiccation as of factor limiting zonation was investigated for 7 South African Patella Linnaeus species. Small specimens lost water fastest and were least tolerant to desiccation. Differences in shell shape largely explain differences in the rate of desiccation, both within and between species: tall conical shells with a small mouth circumference minimize water loss. Tolerance was closely related to zonation, but zonation was not correlated with either shell shape or rate of water loss. Two groups of limpets could be distinguished: migratory species which increase in tolerance as they age, correlated with the habit of moving up the shore; and non-migratory species which have a narrow range of tolerance. Zonation of the former group is probably limited by physical factors while the latter are behaviourally restricted to a narrow zone. The selective value of these strategies is discussed.

Notes: Abstract Sea snakes and file snakes commonly voluntarily submerge (or if on the surface, hold their breath) for periods of 5 to 30 min but may do so for up to about 1 1/2 to 2 h. There is great variability in submergence time, and short apneic periods (several seconds to a few minutes) are not unusual, at least in captivity. Voluntary submergence time is reduced by activity and increased temperature but, if the effects of these two variables are considered, there is no consistent effect of phase of the diel cycle.

Notes: Abstract Growth and metabolism of the winter flounder Pseudopleuronectes americanus were studied in the laboratory at 2°, 5° and 8°C. Dry-weight determinations of growth demonstrated significant direct regressions of growth on temperature. Mean, daily specific growth rates were 10.1%/day at 80°C, 5.8%/day at 50°C, and 2.6%/day at 2°C. Time to metamorphosis was 49 days at 8°C and 80 days at 5°C. Larvae did not survive to metamorphosis at 2°C. Absolute values of routine metabolism expressed in μl of oxygen consumed regressed on body weight were best described by a third-degree polynomial. Larval routine metabolism increased from hatching to metamorphosis, at which time it declined before again increasing. Temperature directly affected routine metabolism. Metabolism on a unit-weight basis decreased with increasing size and was also directly influenced by temperature.

Notes: Abstract In conditions of alternating light and dark, juvenile Penaeus merguiensis de Man are more active during the dark phase. The rhythm persists in continuous dim red light, but not in continuous bright white light. The period of circadian rhythm shown in continuous dim red light varies between individuals from 22.75 to 26.0 h, with a mean of 23.8 h. The response of prawns to an artificially produced tidal situation is mediated by the presence or absence of water flow. No endogenous component of this tidal rhythm was demonstrated. There is an irregular short-term rhythm (period 2 to 3 h). It is suggested that this allows starved prawns to conserve energy.

Notes: Abstract Soy cake* was homogenized and filtered through an 80 mesh net to produce small, detritus-like particles. The effect of soy-cake particles, an artificial detritus, on the survival and growth of Penaeus japonicus Bate zoea was then tested. The soy cake was considered to be effective for survival and growth of the zoea. The best survival rate, 85.9%, was obtained in a tank receiving soy cake in quantities of 0.16 mg/zoea/day. An experiment was also performed to compare three kinds of food: particles of soy cake alone, diatoms (Chaetoceros rigidus) alone, and a half and half mixture of the two. The best growth, 2.49 mm, and the highest survival rate, 79.1%, were found in larvae fed the mixture of soy-cake particles and diatoms. The results thus seem to demonstrate that particles of soy cake could be usefully applied to the mass-culture of the penaeid prawn.

Notes: Abstract Photosynthesis and respiration of 4 species of the marine red algal genus Polysiphonia were evaluated under a variety of light, temperature and salinity conditions. The manometric results were compared with the local distribution and abundance of each species. The species can be separated into two distinct categories based on their overall distribution and temperature optima: (1) cold water plants [P. lanosa (L.) Tandy and P. elongata (Hudson) Sprengel], with peak photosynthesis at 21° to 24°C, but with active photosynthesis as low as 5°C; (2) plants with warm-water affinities [P. nigrescens (Hudson) Greville and P. subtilissima Montagne], having photosynthetic optima at 27° to 30°C, and exhibiting little or no photosynthesis below 10°C. The plants from the first group exhibit thermal injury at temperatures of 25°C and show a narrow tolerance to low salinities during periods of high temperatures. The plants from the second group show thermal injury at 30°C and have a wider tolerance to low salinities. The horizontal distribution of the 4 Polysiphonia species within the Great Bay Estuary System of New Hampshire, USA, is primarily governed by their tolerances to high temperatures and low salinities. The temperature optimum for each of the species corresponds to its particular estuarine distribution. Thus, P. subtilissima, having the highest temperature optimum, penetrated furthest into the Estuary, while P. lanosa, having the lowest temperature optimum, was restricted to the more coastal stations. There was a good correspondence between the natural distribution patterns and the manometric results.

Notes: Abstract The urine and serum compositions in 11 species of Antarctic teleost fishes were studied. The body fluids of these fishes were hypoosmotic to seawater. Both urine and serum osmoconcentrations were conspicuously greater than those of temperate species. The elevated serum osmolality was due to increased levels of NaCl, while elevated urine osmolality was due chiefly to increased concentrations of magnesium and chloride. The kidney was unable to form a urine hyperosmotic to serum under field conditions. The renal tubular epithelium secreted magnesium and calcium against a concentration gradient, while effectively preventing the renal excretion of significant amounts of sodium and potassium. Bladder urine of Antarctic teleosts may often be supercooled by as much as 0.8°C. Coelomic fluid and the integument probably act as a barrier in preventing ice propagation in the supercooled bladder urine, since they both contain glycoprotein “antifreeze” agents.

Notes: Abstract In various months of the years between 1960 and 1972, the R.R.S. “Discovery II” and R.R.S. “Discovery” carried out a number of echo-surveys in the North-eastern Atlantic Ocean between Latitudes 12° and 62°N, and from the European and African coasts to a longitude of approximately 29°W. The prime objective was to acquire data on sea-floor topography. In addition, numerous echo-traces of biological scattering present in midwater between depths of approximately 35 and 460 m were obtained. The traces were of variable quality, but were considered suitable for a preliminary evaluation of the scattering mainly as a basis for further investigation. The scattering recorded in daytime was broadly divisible into three types: (1) Diffuse layers, which were probably due to dispersed single fish. These were not analysed further. (2) Very small discrete echoes, mostly derived from single fish and very small shoals. These were mapped to show geographical regions of greater abundance. (3) Larger discrete echoes, most of which were almost certainly given by fish shoals. These were analysed in detail and information obtained on depth distribution, shoal density, geographical distribution and relative abundance. Small and moderate-sized shoals were found to be very numerous in spring and summer in oceanic water to the West and North-west of the British Isles. Large numbers of shoals of various sizes were also observed at various time of the year in the Bay of Biscay and near certain parts of the European and African Continental Shelf, near certain seamounts, and near islands such as the Azores, Madeira, and the Cape Verde Islands. In general, shoals appeared to be relatively sparse in the more southerly temperate and subtropical regions of the open ocean. The depth distribution of shoals in open water varied greatly but, on average, the maximum daytime depth of those in the more southerly area of the survey was slightly greater than that of those in the more northerly area. Shoal size also varied, shoals to the north of Latitude 50°N were on average slightly smaller than those detected in southerly regins. Possible identification of the fish is discussed.

Notes: Abstract A study was made on the vertical distribution of Chaetognatha in the Hilutangan Channel, based on analyses of 48 plankton samples. Thirty-min horizontal plankton tows were performed at depths of 1, 20, 50, 70 and 100 m in January 1972. Thirteen species of 3 genera of maturing and mature chaetognaths were identified and counted. Sagitta inflata was the most common and abundant species (63.0%), folloed by S. neglecta (9.7%), S. robusta (8.6%), S. regularis (5.4%), S. serratodentata (4.2%), Krohnitta pacifica (2.9%), S. bedoti (2.3%) and S. decipiens (2.0%). S. pulchra (0.7%), S. ferox (0.5%), K. subtilis (0.3%), Pterosagitta draco (0.2%) and S. hexaptera (0.2%) were represented by less than 1% each. Of these 13 species in the upper 100 m, 12 were epiplanktonic while one species, S. decipiens, is generally considered to be mesoplanktonic. Three species were classified as neritic, 3 as neritic-oceanic, and 6 as oceanic, indicating the dominant influence and strong influx of oceanic water into the Hilutangan Channel. Temperature, salinity and dissolved oxygen content did not seem to influence the vertical distribution. Examination of gut contents showed that copepods, followed by arrow worms, were most common in the guts of the chaetognaths studied.

Notes: Abstract The purple seastar Pisaster ochraceus contains clearly measurable protease and amylase activity. Centrifuged supernatants of pyloric caeca homogenates undergo a spontaneous threefold increase in protease activity when incubated under toluene for 50 h at 25°C. Amylase activity remains nearly constant over this period. Bovine trypsin at a 1 to 100 ratio (trypsin to supernatant protein) induces a twofold increase in protease activity over that of the control supernatant while having virtually no effect on amylase activity over the control. The data indicate a specific interaction of trypsin with a protease zymogen rather than a conspecific hydrolysis of membrane components or vesicles by trypsin. Two percent Triton X-100 used as a diluent in place of distilled, deionized water causes a sevenfold increase in protease activity and a twofold increase in amylase activity in pyloric caeca supernatants. The use of Triton as a diluent in the preparation of a stomach-tissue supernatant allows quantitative measurement of both protease and amylase activity in that tissue.

Notes: Abstract The blood circulatory system and the circulatory dynamics of the spiny lobster Panulirus interruptus (Randall) have been examined in detail. A mean absolute blood pressure of 36.5 cm-H2O and a mean pulse pressure of 27 cm-H2O, show this species to have the highest pressure-driven circulation yet measured in decapod crustaceans. Mean blood velocities have been directly measured in intact animals for the first time. These velocities range from over 10 cm/sec in the large arteries to less than 1.0 cm/sec in the sinuses. Total blood volume is variable but averages near 30% of the wet weight, while heart volume averages 0.3% of the wet weight. The blood velocity and volume data are used to compute circulatory parameters such as cardiac output, stroke volume and turnover time. Comparisons with other animals suggest that the so-called “open-system” characteristic of crustaceans may be much more effective than previously supposed.

Notes: Abstract It is the purpose of this paper to elucidate the possible role of the heat resistance level of mature gametes and embryos of poikilotherms in the adaptation of a species to environmental temperature conditions. Within a species, heat resistance of gametes does not undergo any recognisable changes even in the presence of significant fluctuations in temperature. Evidence in support of this statement was obtained on gametes of invertebrates belonging to different populations of the same species collected in different seasons, and on invertebrates maintained under different temperatures. The heat resistance of gametes is correlated with the degree of thermophily of the species concerned. Species living under similar temperature conditions exhibit minimal, if any, differences in heat resistance. Hence, the heat resistance level of their gametes is a function of temperature conditions of formation and existence of the species as a whole. During the ontogenesis of poikilotherms, eggs, zygotes and early stages of embryonic development are most susceptible to heat injury. The upper thermal limit for the normal development of eggs and embryos is only 1 to 3Co higher than the temperatures encountered under natural conditions. It is concluded that the heat resistance level of gametes and embryos represents an adjustment to temperatures at which spawning, fertilisation and earlier embryonal development occur. Temperatures which, throughout the year, exceed the upper thermal limit or remain below the lower thermal limit for the development of embryos, act as limiting factors for the species' distribution.

Notes: Abstract The effects of various heavy metals on light-induced oxygen evolution and on net potassium release were studied in short-term experiments using the unicellular marine algae Dunaliella tertiolecta and Phaeodactylum tricornutum. Heavy metals, except for copper and 3, (3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU) did not cause loss of potassium at concentrations similar to or less than those required for inhibition of photosynthesis. At the concentrations used, no significant loss of potassium was observed for Zn2+, Cd2+, Tl+, Pb2+ nor DCMU. With Cu2+, potassium release occurred at a marginally lower concentration than did inhibition of photosynthesis. The extreme sensitivity of light-induced oxygen evolution to inhibition by cadmium and lead found previously by the author (Overnell, 1974) with Chlamydomonas reinhardii was not found with the strains used here.

Notes: Abstract There exists on Heron Reef, at the southern end of the Great Barrier Reef, an 8-species guild of ecologically very similar, territorial, herbivorous reef fishes. All individuals of these species maintain territories on rubble substrata throughout juvenile and adult life. Territories are defended from all other guild members. Three rubble patches, each containing residents of 3 guild species: Pomacentrus apicalis, P. wardi, and Abudafduf lachrymatus, have been monitored for 12 to 18 months. This paper examines the patterns of use of space as shown by the antecedent and subsequent histories of sites chosen by 43 new colonists, and sites vacated through the loss of 34 residents on the rubble patches. In addition, variation through time is examined in the total amount of space held in territories on each rubble patch. The 3 species show similar preferences for space as colonists, although adult and juvenile colonists behave differently. Numbers of colonists detected on rubble patches are not proportional to the resident populations of the 3 species. Residents of the 3 species are equal in their abilities to enter spaces vacated through mortality, although they differ slightly in methods used to enter sites. They do not respond preferentially to sites previously occupied by any particular species. P. wardi shows a higher rate of mortality than the other species, and residents of this species are more often dislodged by new colonists. The total amount of space held on any rubble patch did not vary during the year from September, 1972 to October, 1973. The data are interpreted as supporting the hypothesis that the 3 species do not differ in their requirements for space on rubble patches, and that they are in competition for a short supply of such space. Differences exist in their strategies for obtaining and holding such space. These differences are important for explaining the continued presence of P. wardi on rubble patches. P. apicalis and a. lachrymatus are both specialists in holding territories on the upper reef slope. No differences have been detected in their requirements or competitive abilities. P. wardi is a fugitive species on the upper reef slope, coexisting because it maintains a refuge from competition by occupying some un-preferred sites off rubble patches.

Notes: Abstract Activities of nitrate assimilation and nitrate reduction were measured 50 cm above the ocean floor (5,845 m and 5,207 m) by an in situ 15N tracer technique at stations in the subtropical (28°29.8′N; 144°58′E) and subarctic (44°10.2′N; 154°03′E) western North Pacific Ocean. Nitrate assimilation ranged from 0.009 to 0.11 μg-at N/1/day, and nitrate reduction from 0 to 0.42 μg-at N/1/day in the presence of added peptone and yeast extract. Nitrate assimilation was higher than nitrite formation at the southern station, but the reverse was the case at the subarctic station. No correlation was observed between bacterial growth and nitrate metabolizing activities. Data are also presented on the effect of hydrostatic pressures upon nitrate metabolism by microbial populations in the surface waters.

Notes: Abstract Total labile organic carbon was estimated in the euphotic zone of the Baltic Sea by a method based on the determination of the biological oxygen demand (BOD); the method is extremely simple, requires little sample water, and is quite precise (±4.5 μmol O2/l or ±40.4 μgClab/l). The amount found was 1,150 μgClab/l, or about 29% of the total organic carbon. At 1 m, a relationship between biological activity, as measured by chlorophyll content, and the amount of labile carbon was found: ln Clab (μg/l)=ln 6.87 (μg/l) +0.272 ln chlorophyll (μg/l), with a correlation coefficient of 0.86, which is significantly greater than zero at the 0.001 level.

Notes: Abstract The community structure and species diversity of hermatypic corals was studied during 1969–1973, in two reef flats in the northern Gulf of Eilat, Red Sea: the reef flat of the nature reserve at Eilat, which is chronically polluted by oil and minerals, and a control reef, located 5 km further south, which is free from oil pollution. In 1969, the nature reserve and the control reef had similar coral community structure. In September, 1970, both reefs suffered approximately 90% mortality of corals, as a result of an unexpected and extremely low tide. In 1973 the control reef was “blooming” with a highly diverse coral community, while almost no signs of coral recolonization have been observed at the nature reserve, and it is significantly lower in diversity. It is suggested that phosphate eutrophication and chronic oil pollution are the major man-made disturbances that interfere with coral colonization of the reef flat at the nature reserve. Although no direct evidence is provided that oil damages hermatypic corals, the data strongly suggest that chronic oil spills prevent normal settlement and/or development of coral larvae. It is possible that chronic oil, pollution results in either one or a combination of the following: (1) damage to the reproductive system of corals; (2) decreased viability of coral larvae; (3) changes in some physical properties of the reef flat which interfere with normal settlement of coral larvae.

Notes: Abstract This paper describes a quantitative investigation of relationships between the growth of phytoplankton, and climatic and hydrodynamci conditions in temperate fjords with marked tides, as exemplified by Puget Sound, Washington (USA). Algal growth in the open waters of the central basin of the Sound is dominated by a number of intense blooms beginning in late April or May and recurring throughout the summer. Rarely, and only briefly, does nitrate become exhausted. The phytoplankton production rate in the central basin of Puget Sound is about 465 g C m-2 year-1. During the springs of 1966 and 1967, oceanographic measurements were carried out at a mid-channel station with sufficient frequency to allow investigation of physical and biological processes with time scales of the order of a day. The principal investigative tool is a numerical model in which the hydrodynamical conditions are represented by an approximate analysis of the gravitational convection mode of circulation. Algal concentration is represented as a continous function of space and time in the model which ascribes changes in phytoplankton density to variations in photosynthetic and respiratory activity, algal sinking, grazing by herbivores, and to mixing and advection. Computations adequately reproduce the principal features of phytoplankton concentrations observed during 75 days and 35 days in the springs of 1966 and 1967, respectively. Numerical experiments assess the relative importance of various processes which govern the level of primary production in Puget Sound. It is concluded that phytoplankton growth is limited by a combination of factors, including vertical advection and turbulence, modulation of underwater light intensity by self-shading and inorganic particulates, sinking of algal cells, and occasional rapid horizontal advection of the population from the area by sustained winds. The high primary productivity of the Sound is due to intensive upward transport of nitrate by the estuarine mechanism. These results should be generally applicable to other temperate fjords because of the largely conventional choice of the biological functions.

Notes: Abstract Changes in tissue weight and in biochemical composition for a standard animal of the bivalve Astarte montagui (Dillwyn) from a station in the Largs Channel in the Clyde Sea Area were studied during 1969–1971. Spawning took place during the autumn months and was accompanied by a decrease in tissue weight which was then continued until March. Tissue weight increased between April and July. A. elliptica (Brown) and A. sulcata (da Costa) from the same area both showed an essentially similar cycle of tissue weight changes, with evidence that spawning occurred during the autumn. The biochemical changes accompanying this cycle, and the resultant changes in caloric content of the tissues are described for A. montagui.

Notes: Abstract Larvae of Bankia gouldi (Bartsch) and Teredo navalis L. were reared in the laboratory at various temperatures and salinities. T. navalis spawned at lower temperatures than B. gouldi. T. navalis larvae were released at temperatures from 13° to 30°C; in B. gouldi, spawning occurred from 17.5° to 30°C. Both species released offspring at salinities of 20 and 30‰. Larvae of the two species can be distinguished morphometrically at the earliest pelagic veliger stage and in the pediveliger stage. Average dimensions of newly released T. navalis larvae are 88 x 75 μ (length x height), while the youngest B. gouldi veligers measure 61 x 50 μ. Pediveligers of T. navalis (205 x 239 μ) are smaller than those of B. gouldi (221 x 260 μ). At other stages of larval development the two species appear so similar that they cannot yet readily be distinguished. Under laboratory conditions of 25°C and 30 ‰, the free-swimming life of B. gouldi to the pediveliger stage was about 10 days longer than that of T. navalis (25 and 15 days, respectively). Incubated larval development of T. navalis was estimated to be 5 days at 25°C. Potential competition between larval stages of the two species, and modification of settling behavior by dissolved humic material (Gelbstoff), is discussed.

Notes: Abstract A laboratory study on the development of Sabellaria vulgaris Verrill, 1873 was conducted to detail such heretofore undescribed post-settling events as the formation of opercular paleae. Culture techniques for the rearing of sabellariid larvae are described. Larval settling behavior is described and the effects of various culturing methods on larval settlement are discussed. Larvae metamorphosed in 19 to 30 days at 21° to 23°C. Metamorphosis involved a loss of provisional setae, anterior rotation of larval tentacles and opercular cirri and a reduction of the episphere. Following settlement, larvae built tubes, lost most of their pigmentation and ciliary bands and added new abdominal segments. Formation of the opercular crown involved the progressive secretion and loss of outer, middle and inner paleae which migrated into the crown after secretion within setigerous sacs. A detailed description of their formation and a discussion of their systematic significance are presented.

Notes: Abstract The feeding biology of the deposit-feeding amphipod Corophium volutator is compared to that of the coexisting, deposit-feeding prosobranch Hydrobia ulvae. Regarding ingestion of particles, both forms show size selection which alone can explain their coexistence. Particle size-selection also explains some qualitative differences in the composition of the food of the two forms; thus, diatoms play a relatively larger role in the diet of H. ulvae than in the diet of c. volutator, whereas bacteria are probably relatively more important for the latter. Results of experiments with feeding of C-14 labelled microorganisms are in accordance with the findings on particle size-distribution of the gut contents, and show that (1) C. volutator can only utilize bacteria adsorbed to particles within the size range 4 to 63 μ (this is why the presence of clay and silt particles in the sediment are necessary for efficient feeding of this amphipod); (2) C. volutator can utilize bacteria suspended in the water pumped through its burrow for respiration if silt and clay particles are present in the sediment. (3) H. ulvae can utilize large particles, and also browses on surfaces, and some evidence is brought forward that it also utilizes mucus for trapping microorganisms. The coexistence of deposit-feeding animals is discussed. It is concluded that the number of coexisting, closely related species is usually small, and that their resource partitioning is probably mainly based on particle-size selectivity. In the case of unrelated forms (e.g. H. ulvae and C. volutator, a number of behavioural, physiological and morphological differences, and also the widespread ability of deposit feeders to utilize alternative feeding mechanisms may also lead to resource partitioning. Thus, there are often several niche dimensions related to feeding allowing a certain diversity of coexisting deposit feeders.

Notes: Abstract Relationships between the types of larval development in 4 species of Littorina from British shores and their inhabitancy of different tidal levels were established by Woodward (1909). His data have led to the view that the Littorinidae present a “text-book” example illustrating obligate interrelationships between the distribution of marine bottom invertebrates in certain biotopes and the possession by them of definite types of larval development. Analysis of data describing larval development of 39 species of littorinids from various regions of the World Ocean covering all its climatic zones, from the tropics to the Arctic, accumulated in the literature (Tables 1-5) demonstrates, however, that there exists only a relationship between viviparity and the inhabitancy of supralittoral zones, and between direct development and the inhabitancy of littoral zones. In 34 out of 39 littorinid species studied pelagic development, in various modifications, is present at all tidal levels; it is most common in the supralittoral zone, but not in the sublittoral zone, as has been generally assumed. The data presented in Tables 1-5 confirm the author's opinion (Mileikovsky, 1971, 1973) that the concept of obligate interrelationships between definite types of larvel development in marine benthic invertebrate and their existence in definite biotopes, based on Woodward's scheme, is false and must be rejected.

Notes: Abstract The fresh-water field crabs Paratelphusa hydrodromous were acclimated to different concentrations of artificial sea water. In vitro polysaccharide synthesis of muscles in medium enriched by insulin or eyestalk extracts was studied at different temperatures. In crabs adapted to increased salinities, the polysaccharide content is higher in the extensor than in the flexor muscle. Adaptation to high salinities reduces the muscle polysaccharide content. In vitro polysaccharide synthesis is greater in the extensor muscle; the rate of synthesis decreases as the adaptation salinity is increased. The hemolymph sugar level does not vary with salinity. Eyestalk extract accelerates the synthesis rate in muscles more than does insulin. These changes are discussed with reference to potential mechanisms underlying non-genetic adaptation.

Notes: Abstract The effects of starvation on the levels of protein, carbohydrates and lipids of three principal reserve compartments-the gonads, digestive tract, and test-have been studied in the resting stage of the sea urchin Arbacia lixula. Variations of these levels were observed during 1 month's starvation. Analysis of covariance revealed the following significant changes: (a) a decrease in carbohydrates of the test and digestive tract; (b) a decrease in lipids of the test and gonads; (c) an increase in proteins of the gonads. A decrease in the carbohydrates and lipids of the test during the first week of starvation emphasizes the importance of the test as a storage organ.

Notes: Abstract A mathematical model is presented of the ecosystem in the upper layers of the marine pelagic zone. The model has been constructed on the basis of presumed connections between biotic and abiotic ecosystem parameters typical of the Black Sea. Details on total model relations as well as on model analysis and construction may be obtained after gaining more insight into the behaviour of models constructed for the upper pelagic ecosystem of different marine aquatoria. The model is characterized by a rather complex behaviour. Realization of the model on the electronic computer is made by employing the method of random trajectories. As a result, a qualitative picture of model behaviour under different conditions is revealed and statistical characteristics of the parameters are obtained.

Notes: Abstract The effectiveness of the Gatun Lake fresh-water barrier to fish migration of the Panama Canal was examined, based on literature records and recent collections. Six species have migrated to the Pacific and three to the Atlantic Oceans. New records include: Hypleurochilus aequipinnis, Barbulifer ceuthoecus and Oostethus lineatus of Atlantic origin, and Gnathanodon, speciosus of Pacific origin. The majority of Atlantic migrants are known in the Pacific only from the Miraflores Third Lock, a unique ectogenic meromictic lake attached to the Pacific entrance of the canal. The hydrography and biota (including Atlantic algal and crustacean species previously unknown as canal migrants) of the lake are discussed. It is presumed that certain fish migrants transited the canal by associating with fouling material on the underside of ships. The euryhaline species, H. aequipinnis, Lupinoblennius dispar, Lophogobius cyprinoides and Omobranchus punctatus survived in freshwater (0.0‰S) for periods longer than réquired for ship transit of the canal (ca. 8h). The stenohaline migrant Gobiosoma nudum died after 2 h in freshwater, but survived more than 50 h at 2.5‰S. Plans to increase Panama Canal ship transits through the pumping of seawater into Gatún Lake might remove the biological barrier and allow the migration of euryhaline and stenohaline species. We find those plans unwise, and the potential consequences dangerous.

Notes: Abstract A light and electron microscope study was conducted on Nicolea zostericola (Oersted: Grube, 1860) to describe the processes of gametogenesis. N. zostericola is a monotelic species which spawns from 2 to 5 times over a period of 2 weeks at the end of its 1-year life span. The gonads consist of plates of cells bulging from beneath the peritoneum in the thoracic region of the body. Oogenesis has been divided into 3 phases: an ovarian phase in which gametogonia and primary oocytes are retained within the ovary, a follicular phase, in which oocytes are ovulated into the coelom surrounded by several layers of follicle cells and the vitellogenic phase, where individual oocytes rupture through the follicle cells and enter the coelomic fluid where cell growth and yolk synthesis occur. The combined ovarian and follicular phases have a duration of about 3 to 5 weeks and the vitellogenic phase about 5 to 6 months. Vitellogenesis is described on the ultrastructural level. Yolk synthesis involves the participation of the Golgi apparatus and endoplasmic reticulum of the oocyte in possible combination with nutrient absorption from the coelomic fluid. Spermatogenesis involves the rupturing of masses of spermatogonia into the coelom from the testis, surrounded by peritoneal cells. Smaller clusters of spermatocytes are later released into the coelomic fluid where mitotic and meiotic divisions eventually produce flattened plates of sperm. The mature spermatozoan possesses an elongate head, atypical for most polychaetes.

Notes: Abstract Growth experiments in batch cultures indicated that the uptake of nitrate by the marine pseudomonad PL1 was inhibited in the presence of ammonia provided that the ammonia concentration was higher than 1 mM. At ammonia concentrations of less than about 1 mM, however, both nitrate and ammonia were utilised simultaneously. The saturation constants for nitrate and ammonia uptake were both 2.6x10-4 M, and similar to the Michaelis constants of nitrate reductase for nitrate (2.9x10-4 M) and glutamine synthetase for ammonia (2x10-4 M). Nitrate reductase activity linked to NADH was detected in chemostat-grown cultures with nitrate as nitrogen source, and in cultures containing limiting concentrations of nitrate and ammonia, ammonia or glutamate. Enzyme synthesis appeared to be repressed in cultures containing an excess of ammonia or glutamate. Chemostat cultures utilised ammonia or glutamate in preference to nitrate, while there was no marked preference between ammonia and glutamate.

Notes: Abstract The “resting” eggs of a marine neritic copepod, Tortanus forcipatus Giesbrecht, recovered from sea-bottom sediment were hatched in the laboratory. Hatching occurred at temperatures of 13° to 30°C, no eggs hatched at 10°C. Temperatures around 25°C were found to be optimal for hatching, although the range of optimal temperatures for hatching was approximately 5°C lower in eggs stored for 14 to 15 months than in those stored for 1 to 2 months. A wide range of salinity, from 18 to 54%S, was favourable for hachting. Eggs failed to hatch within the sediment mud, which suggests that they are in a state of dormancy in the mud. Hatching was successful under both light and dark conditions.

Notes: Abstract The seasonal cycles of abundance of populations of dominant calanoid copepods in the water column and of their eggs recovered from the bottom sediment in the central part of the Inland Sea of Japan are described. The numbers of both copepods and eggs fluctuated markedly with season in an essentially similar pattern among the 6 species studied (Tortanus forcipatus Giesbrecht, Calanopia thompsoni A. Scott, Acartia erythraea Giesbrecht, A. clausi Giesbrecht, Centropages abdominalis Sato, C. yamadai Mori). The density of eggs in the sea bottom was highest shortly before the population of adults and late copepodids disappeared from the plankton; the numbers of eggs then gradually decreased until the appearance of the next planktonic population.

Notes: Abstract Lipid analyses were carried out on various species of zooplankton captured in Saanich Inlet, British Columbia, Canada, during September, 1972. The amphipod Cyphocaris challengeri had the highest level of lipid, consisting mainly of wax esters. The copepod Calanus pacificus had moderate amounts of lipid, with triglyceride as the major neutral lipid. The euphausiid Thysanoessa raschii contained mainly triglyceride in its moderate levels of neutral lipid, while wax esters and, to a lesser extent, triglycerides were present in the very small levels of neutral lipid in the chaetognath Sagitta elegans. The major fatty alcohols in wax esters of both Cyphocaris challengeri and Calanus pacificus were 20:1 and 22:1, although notable differences were found in the major fatty acids. Biosynthetic studies showed that phospholipids were labelled faster than neutral lipids in all species with both (U-14C) glucose and (1-14C) palmitic acid as precursors. Only species containing significant amounts of wax esters in their neutral lipids incorporated substantial amounts of radio-activity from (1-14C) palmitic acid into wax esters in (i) living animals, (ii) preparations containing fragments of tissue, (iii) cell-free systems. All species incorporated added fatty alcohols into wax esters in preparations containing tissue fragments and in cell-free preparations. Both the fatty acid and fatty alcohols of the wax esters of both Calanus pacificus and S. elegans were labelled from (1-14C) palmitic acid, consistent with de novo biosynthesis of the esters. (1-14C) hexadecanol was incorporated into wax esters almost entirely in the fatty alcohol moiety. It is concluded that all species examined formed was esters when presented with preformed fatty alcohols, but only those species that had wax esters as a major component of the neutral lipids were capable of de novo biosynthesis of the lipids.

Notes: Abstract Fourteen species of sergestid shrimps were collected in the Sargasso Sea between the surface and 1500 m near Bermuda on 4 cruises. The vertical distribution and feeding activity of the most abundant species are discussed in relation to interspecific competition and the adaptive significance of vertical migration. Each species lives within a narrow depth range and exhibits a diel vertical migration. Sergestes splendens migrated as much as 825 m, while S. japonicus migrated less than 100 m. Neither the seasonal nor permanent thermocline influenced the migration range. The only species which occurred together both day and night were S. pectinatus with S. vigilax and S. pectinatus with S. sargassi. Morphological differences in the third maxillipeds of these species suggest differences in feeding. Although most species eat a variety of organisms, the foreguts of S. grandis, S. corniculum, and S. splendens contained euphausiids more often than those of other species, and S. grandis and S. robustus fed more frequently on fishes. In contrast, S. japonicus appears to feed on detritus. Food was found in the foreguts of most species less frequently during the day than night, but no species fed only at night. S. sargassi and S. pectinatus fed equally day and night.

Notes: Abstract The relation of shell form to habitat in the Mediterranean limpets Patella caerulea (L.) and P. lusitanica (Gmelin) was investigated. P. caerulea shells were significantly longer, broader, but lower in height than P. lusitanica shells. The regression of the ratio (length plus breadth)/2 on the height of the shell was found to characterize the two limpet populations, with a small degree of overlap reflecting the distribution of the two limpets on the shore.