ALBERT

Notizen: Summary Trichopsis pumilus has the same system of sound production asTrichopsis vittatus but with morphological differents. As distinguished fromTrichopsis vittatus muscels and tendons of the sound producing mechanism in femals ofTrichopsis pumilus are very reduced. Therefore probable femals ofTrichopsis pumilus are not able to produce sounds.

Notizen: Summary Various types of surface microstructures and their distribution in the Giant Antarctic SlaterGlyptonotus antarcticus Eights, 1852, are described in detail. Although no attempt has been made to classify the different kinds of scales, leaf-like modifications, threads and feathery hairs, ideas concerning their origin and their function are presented. At least some of the microstructures described seem involved in discouraging foraminifera and larval stages of sessile organisms to settle upon the cuticle ofClyptonotus.

Notizen: Summary The ultrastructural features of oogenesis were examined in the spionid polychaeteStreblospio benedicti. Paired ovaries are attached to the genital blood vessels extending into the coelomic space from the circumintestinal sinus. The genital blood vessel wall is composed of flattened, peritoneal cells, large follicle cells and developing oocytes. Vitellogenesis occurs while the oocytes are attached to the blood vessel wall. Two morphologically distinguishable types of yolk are synthesized. Type I is synthesized first by an autosynthetic process apparently involving pinocytosis and the conjoined efforts of the Golgi complex and rough endoplasmic reticulum. Type II yolk appears later through a heterosynthetic process involving the infolding of the oolemma and the sequestering of materials from the blood vessel lumen by endocytosis. During this process, blood pigment molecules appear to be incorporated into endocytotic pits, vesicles and eventually the forming yolk body. The significance of heterosynthetic yolk formation to the general reproductive strategies of polychaetous annelids is discussed.

Notizen: Summary An ocellus of an anthomedusan, Nemopsis dofleini, is composed of sensory and pigment cells and underlain by a nerve plexus and a muscle sheet. A sensory cell is divided into three parts: an apical part from which a single cilium arises, a slender middle part with numerous microtubules and an enlarged basal part that contains an oval nucleus but does not send out an axon. The ocellar cup is occupied by variously remodelled ciliary sheaths that are covered by a few lysosomal projections from the pigment cells. Three modes of synaptic connections — centripetal, centrifugal and two-way — are found between sensory cells and either dendrites or somata of second order neurons. Synaptic vesicles in sensory cells are larger in number, smaller in size and more uniform in shape than those of second order neurons. The soma of a second order neuron lies below the surface layer of an ocellar cup and gives rise to a single cilium that lacks rootlets and the second centriole. The possibility of multimodal sensory perception in and around the ocellar region is discussed.

Notizen: Summary The whip organs are situated proximally on the ventral side of most segments of the whip scorpion's whip. As the cuticular layer covering these organs is much thinner than the usual cuticle, the whip organs may be recognized easily under the light microscope as oval regions. The study of the ultrastructure reveals an epithelium characterized by apical and basal invaginations of the cell membrane with numerous mitochondria and prominent whorls of smooth endoplasmic reticulum. Thus, the whip organs possess the characteristics required for transepithelial transport processes. The possible function is discussed, based on experimental study.

Notizen: Summary Structure and ultrastructure of the papillae in the mantle epithelium of the polyplacophoranAcanthochiton fascicularis are described. They consist to a major part of various secretory cells. Visual cells occur frequently in the papillae. Each of these organs form up to a few spines which have basally a cup of organic material. This connects the calcareous spine with the spine cell and often with a second cell which has distally one cilium. They are tactile receptors. Other spines are only for the defense and can be moved by muscles. They continue to grow basally in contrast to the tactile spines which are pushed off after some time and replaced by new ones formed in the papillae. The aesthetes and the mantle papillae are homologous organs.

Notizen: Summary The mature male nephridia ofPolydora ligni andP. websteri (Polychaeta: Spionidae) are segmental organs composed of a ciliated nephrostome connected to a nephridial canal that crosses the intersegmental septum, expands into a large modified part extending dorsally through the coelom and subsequently narrows into a canal terminating in a dorsal nephridiopore. The nephridial canal is ciliated throughout and is composed of several cell types. Cells in the expanded region of the nephridia of both species contain large urn-shaped depressions filled with long microvilli. InP. ligni, one section of a nephridium contains cells packed with electron-dense granules that are not observed inP. websteri. The spermatophores ofPolydora ligni are composed of a central sperm mass surrounded by a layer of randomly oriented tubules that form a capsule around the sperm and taper into a long thin tail. These tubules are identical in dimensions to the microvilli present in parts of a nephridium and apparently are derived from these microvilli. The spermatophore capsule ofP. websteri is composed of similar tubules also presumed to originate from nephridial microvilli. The microvilli in nephridia of both species are surrounded with a glycocalyx that may function as an adhesive to hold the spermatophore capsule together. This glycocalyx may also function as a species specific message when encountered by a receptive female.

Notizen: Summary The internal and external structure of the galeae of the adult red turnip beetle, Entomoscelis americana, was studied using SEM and TEM. The galea broadens from base to truncated tip and its sides are of thick, sculpted cuticle invested with pores and coarse spines. The tip is of thinner, flexible cuticle covered with 8–12 uniporous, blunt-tipped apical pegs and a single, aporous, sharply-pointed apical hair. The coarse spines are singly innervated probable mechanosensilla owing to the tubular body at the distal end of the dendrite. These sensilla likely act as tactile hairs monitoring galeal-effected movements of food particles into the functional mouth. The pores are associated with glands within the galea. The function of the presumed secretion is not known but may be to keep objects and dried saliva from sticking to the mouthparts. The apical pegs are innervated by five neurons, each producing a single dendrite. Four dendrites enter the single peg lumen and communicate with the terminal pore. The fifth differentiates into a tubular body that inserts into the peg base. These are typical insect contact chemosensilla that, because of their location, would taste incoming food. The apical hair has no pores but is innervated by two neurons, each extending a dendrite into the hair lumen in chemosensillar fashion. The sensory mode of this sensillum is unknown but is probably not mechanoor chemoreception. Many of its features, reminiscent of taste hairs, lead us to hypothesize that it represents a one-time chemosensillum recently modified to a new form and sensory mode. Because larval and adult E. americana share similar food plant requirements, we hypothesize that similarities will be seen in their mouthpart sensilla. Comparisons of the adults and larvae show the common features between their respective galeal taste hairs are only those of insect contact chemosensilla in general. However, the adult apical hair and the larval medial sensillum show striking specific structural similarities. We propose that these are true structural and functional homologues.

Notizen: Summary The wall of the sinus venosus in an elasmobranchian species, Chimaera monstrosa L. is described. Endocardial cells contain numerous large vacuoles, as well as a number of membrane-bounded, moderately electron dense bodies (MDB). Myocardial cells lie closely packed into bundles surrounded by a basal lamina of about 20 nm thickness, and by large amounts of collagen fibres. These cells are connected by desmosomes of 1–2 µm length and with an intermembranous gap of 10–20 nm. Myocardial cells poor in myofibrils are intermingled with cells containing a well developed contractile material. Atrial specific granules are scarce. Vesiculated nerve processes occur at a distance of about 20 nm from the myocardial sarcolemma. Myocardial cells of the sino-atrial junction appear ultrastructurally similar to those located elsewhere in the sinus venosus. Epicardial cells contain large vacuoles, and have fibrecoated protrusions extending into the pericardial space. The possibility of pacemaker activity in the elasmobranchian sinus venosus is discussed.

Notizen: Summary The nature and homologues of the appendages of the anterior end of the polychaete families Sabellidae and Serpulidae have long been discussed. The main purpose of the present investigation, in which seven sabellid and eight serpulid species are studied, is to contribute towards the solution of these problems. At the same time, however, the present study, within its limited range, aims to enlarge our knowledge of the anatomy of the polychaetes in general. Such a knowledge, it is argued, is a prerequisite for further consideration of the phylogeny of the Polychaeta. As shown in many earlier papers, the architecture of the cephalic nervous system and the innervation of the organs and appendages of the anterior end of polychaetes constitute reliable instruments for elucidating the morphological significance of these structures. In the present paper, consequently, extra consideration is given to descriptions of the central nervous system of the sabellids and serpulids studied. The integumental depression found in front of and below the brain of all the sabellids and serpulids here studied is described by the term “dorsal pit”. It is concluded that the dorsal pit within each family in all probability represents a homologous structure, but it is in no way proven that the dorsal pit of the sabellids is equivalent to that of the serpulids. Some earlier literature maintains that paired antennae [antennes de première paire in Binard and Jennerś (1928) terminology] are found in some sabellids and serpulids. In the present paper it is maintained that these structures must instead be interpreted as nuchal organs. Such organs are found in all the sabellid and serpulid species here studied. The Pruvot-Meyer theory which claims that the joint pore of the thoracic nephridia of the “serpulimorphic” families is equivalent to the nuchal organ of other polychaetes is shown to be without foundation, and it is consequently rejected. The histology, vascularization, and innervation of the branchial crown and the appendages of the dorsal lip of the mouth of the species investigated are described. It is concluded that the branchial crown and some (but not all) appendages of the dorsal lip are equivalent to the palps (when present) of the “spiomorphic”, the “drilomorphic”, and the “errant” polychaetes. The appendages of the dorsal lip of the mouth, in most faunistic literature called palps, are found to represent structures of three different kinds and origins: (a) branchial radioli which have become separated from the crown and have fused with the lip, (b) branchial pinnulae which have undergone a similar process of dislocation, and (c) new formations from the walls of the mouth cavity. It is proposed that in comparative-anatomical works these appendages should be called (a) lip-associated radioli, (b) lip-associated pinnulae, and (c) outgrowths of the dorsal lip respectively. As a joint and anatomically neutral term to be used in faunas and descriptions of the outer morphology, the expression “appendages of the dorsal lip” or, more briefly, “(dorsal) lip processes” is proposed. The interrelationships of the Sabellariidae, the Sabellidae, and the Serpulidae are discussed, as is the taxonomic subdivision of the last two families. In agreement with some earlier authors although contrary to others it is thereby maintained that: 1) the suborder Serpulimorpha Hatschek (1893) (inclucing sabellariids, sabellids, and serpulids) does not constitute a natural systematic unit; 2) the sabellids and serpulids, although markedly different in many respects (thoracic membrane, operculum, branchial skeleton), are probably closely related to each other. Earlier arguments supporting this view are corroborated by data on the dorsal lip processes and the architecture of the brain of the two families; 3) Rioja's (1923) division (based on setal structures) of the Sabellidae into the three subfamilies Sabellinae, Fabriciinae, and Myxicolinae is supported by the anatomical data emphasized in the present paper; and 4) within the Serpulidae the genera Apomatus and Protula should be referred to the subfamily Filograninae [as proposed by Rioja (1923), followed, among others, by Fauvel (1927), and Hartmann-Schröder (1971)] and not to the Serpulinae, [as maintained by Hartman (1959) and Fauchald (1977)]. Again, the view presented by the present author is founded on anatomical data (the morphological value of the dorsal lip processes of the genera in question).

Notizen: Summary The amphipod species Haploops tubicola has an unusual compound eye that is divided into three separate parts, each with one common cuticular lens. The dorso-frontal eyepair has, in addition to the lens, a so-called vitreous body, which is constructed like a dioptric lens and is inserted in the ray-path. The ‘vitreous body’ is actually — and for which evidence is presented — a secretory product formed in the intercellular spaces of the organ of Bellonci. Histochemical analysis has shown that the secretion is strongly PAS-positive and lacks glycogen.

Notizen: Summary Linear viscoelastic properties of laboratory handsheets have been investigated from the two dimensional aspect. According to the linear theory of viscoelasticity, the behavior of transverse isotropic materials such as handsheets subjected to plane stresses is fully described by the two in-plane relaxation functions G11 (t) and G12 (t). In the present paper, some viscoelastic characteristic functions describing responses to in-plane deformation histories are derived from G11 (t) and G12 (t) determined by strip biaxial stress relaxation testing. The predicted uniaxial relaxation function curve was in good agreement with the experimental one, and the viscoelastic Poisson's ratios in uniaxial stress relaxation and in uniaxial constant strain rate extension were decrease functions of time. Effects of beating on the areal dilatation and shear relaxation functions are discussed by introducing the classical concept of relaxation spectrum.

Notizen: Summary This electron microscopy study is concerned with the dormant cambial cells in compression wood of Picea abies (L.) Karst. The cambial zone comprised 4–8 rows of fusiform cells. Each radial file contained the group known as Sanio's four, namely an initial, a mother, and two daughter cells. Groups of three, resulting from a failure of a mother or a daughter cell to divide, were also present. Undifferentiated xylem tissue cells occurred singly, in pairs, or in groups of four. These cells and the last-formed tracheids were often enclosed by a common primary wall. The fusiform cells had a large, elongated nucleus, numerous small vacuoles, and a frequently infolded plasma membrane. Golgi apparatus and endoplasmic reticulum were rare, while plastids, amyloplasts, and lipid droplets were common. Cambial ray cells contained much lipid material. The tissues were similar to cambial tissues in normal wood of conifers. The present results can only be interpreted in terms of the single layer of initials and sequence of cell divisions established by Sanio. The initial can be located by several criteria in dormant and active cambial regions in conifers. It could be shown that the existence of the group of Sanio's four is better documented in the literature than has so far been recognized. The occurrence of a variable number of primary cell walls is discussed with reference to the concentration of lignin in the middle lamella of mature xylem.

Notizen: Summary The technology and chemistry of recent advances in alkaline pulping are reviewed from the standpoint of the authors' work over the past few years. Topics reviewed include soda-amine [particularly soda-ethylenediamine (EDA)], soda-anthraquinone (AQ), kraft-AQ, and soda-AQ/EDA pulping and their effects on pulp strength properties and bleachability. There is evidence to support the concept that the rates of all alkaline delignification reactions, including kraft, are controlled by a reductive step which transfers electrons to the degrading lignin.

Notizen: Summary A lignin-carbohydrate material from black spruce (Picea mariana) was treated with a hemicellulase mixture. The carbohydrates in the remaining material were studied by the following methods. a) Treatment with 0.1 M NaOH in the presence of sodium borohydride followed by selective hydrolysis of the furanosidic bonds, b) Smith degradation (periodate oxidation followed by mild acid hydrolysis). The results obtained indicate that lignin is bound to all types of sugar units in the hemicelluloses. For arabino-4-O-methylglucuronoxylan, linkages to the side-chain units seem to dominate. The links to the 4-O-methylglucuronic acid units are ester bonds, probably benzyl ester bonds. Those to the other sugar units in the hemicelluloses are ether bonds, probably benzyl ether bonds. The results suggest, furthermore, that fractions of cellulose are linked to lignin.

Notizen: Summary NPA, applied in a 2–3 cm band around the middle protion of 2- or 3-year-old internodes of three vertically-oriented six-year-old Sugi trees (Cryptomeria japonica D. Don), brought about abnormal thickening all over the upper segment from the NPA treatment. Xylem tissues above and below the treatment, as well as at the treated area itself, was examined by ordinary light microscopy and by scanning electron microscopy. The results obtained seemed to indicate that the tissue formed after treatment in the upper segment of the stem was true compression wood. In the lower segment of the stem, no abnormal tissue but a small amount of latewood-like tissue was produced after treatment. Referring to the previous studies in which morphactin, another IAA transport inhibitor, has induced compression wood, we consider it likely that compression wood formation must be induced by high concentrations of endogenous IAA, which could be brought about by blockage created not only by NPA and morphactins, but also by IAA transport inhibitors in general.

Notizen: Summary Tangential latewood sections (60 μm) of Scots pine sapwood were differently treated with chlorite. The subsequently incubated two strains of Bacillus polymyxa caused a weight loss up to about 25%, including a loss of lignin of about 42%. UV-microspectrophotometry of 1 μm-cross-sections prepared from the cultured woody tissues demonstrated that bacteria caused neither quantitative nor qualitative changes of the remaining lignin. The lignin, which was dissociated from the pretreated woody cell wall by bacteria, could not be respired, suggesting that the lignin is a ‘ballast’ to these bacteria that inhibits the dissimilation of the carbohydrates in the wood.

Notizen: Summary The paired buccal ganglia ofHelix pomatia were investigated by light microscopical methods. Number and location of the buccal nerves show a certain variability. The caudal surface of the buccal ganglia was standardized, and the location of single neurones and groups of neurones was entered in the standard sketch. Normally there were found four giant neurones (B1–B4, diam. 120–170 μrn) in each ganglion, three of them in the lateral lobe and one (B4) in the medial lobe. The run of the nerve cell processes of B1–B4 was traced with the aid of retrograde filling with CoCl2 or in series of toluidine blue stained semithin sections. The run of the axons of B1–B4 proved to be constant. The nerve cell processes of each B2 project into both ipsi- and contralateral first salivary gland nerves. Obviously the salivary glands of each side are innervated by both right and left B2. Besides the four giant neurones two characteristic nerve cell groups (diameter of the perikarya 20–30 μrn) could be localized. The staining properties (paraldehyde fuchsin-positive) suggest, that one cell group contains peptidergic neurosecretory material. The second cell group contains catecholamines as it was shown with the aid of formaldehyde induced fluorescence. The results are discussed with findings of different authors at different slugs and snails, to point out homologies in the cellular organization of the buccal ganglia.

Notizen: Summary The ultrastructure of the auricles, the ostia, and the ventricle of L. asellus and T. marmorea is described. The heart wall consists of an epicardium, a basement membrane, and an inner loose myocardium. The epicardial cells of the auricle are podocytes. The exposed cell body and the branched processes show pedicles. Ventricular epicardium is flat and simple. The slender, unbranched, mononucleated muscle fibres have a peripheral nucleus located midway along the fibre. Mitochondria are peripherally located, leaving the center to longitudinally running thick and thin myofilaments. Dense bodies and attachment plaques make up the Z-material. Sarcomeres and myofibrils are absent, as are transverse tubules and intercalated disks. The sarcoplasmic reticulum consists of peripheral tubules and subsarcolemmal cisternae, some of which radiate, branch, and run between myofilaments. Couplings are lacking. Ventricular fibres in T. marmorea show nexuses and desmosomes; in L. asellus only nexuses. The muscular ostia are tubular, and muscle fibres resemble those of the ventricle; nexuses are detected in T. marmorea and desmosomes in L. asellus. The only nervous elements observed are some nerve processes, structurally similar to those of other molluscs.

Notizen: Summary The neuropile regions in the supraesophageal ganglion ofLocusta migratoria were revealed by Bodian staining of frontal and parasagittal sections. A combined recording and staining technique (CoS method, Rehbein et al., 1974) was used to identify physiologically five different types of auditory ventral cord neurons and mark the course of their axons and the positions of the terminal arborizations. The boundaries of the projection regions are described; they include the various multimodal neuropile regions in the ventrolateral protocerebrum. Previously demonstrated instances of convergence with neurons of other sensory systems, and others likely to exist, are considered with respect to their possible significance in neuronal processing within the auditory system.

Notizen: Summary The branchial vasculature of the smooth toadfish,Torquiginer glaber, was studied by light microscopic examination of Microfil vascular casts, and scanning electron microscopy of critical point dried tissue and vascular corrosion casts. The anatomy of the respiratory vascular bed was similar to that described for other teleosts. An extensive non-respiratory vascular bed was also present in the gills. In each filament this comprised a series of capillaries arising mainly from the efferent side of the gill circulation (efferent filament artery, efferent lamellar arterioles, branches of the efferent branchial artery), but also from the afferent side (afferent filament artery, afferent lamellar arterioles, lamellar blood channels). The capillaries eventually connected to a system of broadly interconnected sinuses in the filament termed the central canal and the afferent and efferent companion vessels. The sinuses connected with a large subepithelial sinus and a pair of venolymphatic vessels in the gill arch. Connections between the subepithelial sinus of the arch and the anterior venous system were demonstrated. It is suggested that the non-respiratory capillaries serve a nutritive function, while the filament sinuses provide a combined venolymphatic drainage for the filament.

Notizen: Summary The hyomandibula is an important element of the head and has been influenced in its structural features by different functions. It is roughly T-shaped with vertical and horizontal ridges. In fish, such asMacropodus opercularis, the deep curve at the antero-dorsal end of this ridge may be correlated with the concentrated force applied by the adductor mandibulae muscles. InMacropodus opercularis, the hyomandibula is shorter and broader than that ofAnabas testudineus andCtenopoma acutirostre. In the latter two genera, almost the entire anterior surface of the vertical ridge is uniformly curved, which may be explained by the distributive force applied by the adductor muscles perpendicularly. InMacropodus, the hyomandibulo-interhyal articulation is not straight along the axis of the interhyal as inCtenopoma, but the interhyal makes an angle of 45

Notizen: Summary The types of cell death in the midgut epithelium of the worker honey bee during the larva-to-pupa transformation were analyzed by light and electron microscopes. The metamorphosis begins with an increase in the number of autophagic vacuoles in larval epithelial cells and terminates with lytic destruction of the whole intestinal epithelium. Apoptosis seems to be independent of cell age, but important in fashioning of the new organ. Even in the cells in the regenerative nests of the larval epithelium, from which the pupal epithelium develops, apoptotic death occurs. Single apoptotic cells are eliminated gradually from the primary multilayer tissue until the monolayer pupal epithelium is formed. Some of the apoptotic cells are endocytosed by sister epithelial cells.

Notizen: Summary 1. Exocrine glands found in the anterior hindgut of the millipedesPolydesmus angustus andGlomeris marginata should be termed pyloric glands. 2. The pyloric glands ofPolydesmus angustus are appropriately differentiated hindgut epithelial cells. Every single cell shows secretory activity. 3. InGlomeris marginata the pyloric glands are composed of three types of cells: secretory cells, transitional cells, and canal cells. 4. The size and form of the pyloric glands are related to the length of the hindgut. 5. The secrete of the pyloric glands is dispersed on the hindgut intima as a thin film. 6. This secretion layer seems to influence the permeability of the hindgut and play an essential role in the reabsorption of water and other important compounds.

Notizen: Summary Adhesive organs of 17 gastrotrich species of the order Macrodasyida and 2 species of the order Chaetonotida (Chaetonotida-Paucitubulatina) can be seen by transmission electron microscopy to comprise two gland cell types. These cells are morphologically similar to viscid and releasing glands of the Turbellaria and so are identified by these same names; the adhesive system in these gastrotrichs is therefore called a duo-gland system considered at least functionally comparable to the duo-gland organs of turbellarians. The two gland cell types project their necks through tubiform extensions of the animal's cuticle. Some adhesive tubules have only one of each gland type; others, even in the same species, may have two viscid and one releasing glands; and compound organs such as posterior footlike appendages may have three and four viscid glands and one releasing gland per tubule. Gland cells in some species have fibers, evidently cytoskeletal in function. The adhesive tubules are quite similar in all of these species and provide few characters for determining within-group relationships of the gastrotrichs. The duo-gland system of the Gastrotricha is probably not homologous with that of the Turbellaria.

Notizen: Summary The water-conducting system ofEphydatia fluviatilis includes sluice-like structures at the critical sites, some of them at the surface of the sponge and some inside it. These are dermal pores, pores in the walls of the inhalant and exhalant canals, and the osculum. The characteristic common to all of these openings is the porocyte, a disk-shaped cell with an aperture in the middle, so that it has an annular appearance. The shape and fine structure of the cells with pores, as well as their position in the pinacocyte epithelium and the impermanence of at least the dermal pores, indicate that these cells are regular pinacocytes serving a special function. The porocytes in the walls of the exhalant canals always appear in association with a flagellated chamber, with which they are connected by way of two or three modified choanocytes that form a double cone. The osculum at the distal end of the egestion passage, is the product of two porocytes, derived from the exopinacocyte and the endopinacocyte epithelia and having congruent apertures.

Notizen: Summary The morphology and ultrastructure of the ovarioles ofRaphidia flavipes are described. The ovary ofRaphidia shows all the structural elements by which the telotrophic ovarioles of Megaloptera can be distinguished easily from those of polyphage Coleoptera or Hemiptera. This supports the view of sister-group relationship between the Raphididae and the Sialidae.

Notizen: Summary On the antennulae ofLeptestheria dahalacensis (Conchostraca) nearly 600 sensory setae of one type are found. They are gathered in groups of 25–30. The single sensory seta is divided into two parts by the basal bead which is easily visible in the light microscope. The basal bead is the socket of the seta, whose wall is mainly built up by the epicuticle. The terminal pellet closes the tip of the seta. The basal bead is derived from the innermost layer of the epicuticle. 4–10 dendrites each with one receptorcilium innervate the receptor. The receptorcilia stretch through the interior part of the receptor and the basal bead into the exterior part, where they branch. They enter the terminal pellet in a porus, which seems to be a moulting porus. The interior part of the receptor is surrounded by 5 sheath cells. During the premoult it becomes obvious, that the socket of the seta is built by the sheath cell 5, the basal bead by the sheath cell 4 and the shaft by the sheath cell 3. For this the sheath cell 3 is divided into two parts. Between this two parts the newly formed cuticle is invaginated. The sheath cell 2 formes the tip and the sheath cell 1 the cuticular sheath of the new bristle.

Notizen: Summary A comparative ultrastructural study of trunk segments of a variety of small polychaetes (body diameter less than 250 μrn) was undertaken to determine whether small body size is correlated with deviations from the typical annelid pattern of coelomic organization. Peritoneum is never found covering oblique or parapodial muscles traversing the body cavity. Aside from this, two major patterns of body cavity organization are seen: 1. spacious body cavity with varying extent of peritoneal lining (complete, partial, absent) and 2. the body tending toward the acoelomate condition, as a result of the expansion of lining cells or the lack of initial cavity formation. The significance of these anatomical variations is discussed with respect to functional and phylogenetic considerations.

Notizen: Summary Woodlice are unique among the arthropods in moulting in two halves. The intramoult is 1.8 days inOniscus asellus and results from the two halves being out of synchrony throughout the cycle. In the integument, the initiation of a new moult cycle is heralded by epidermal cell vacuolation; a little later, the subepidermal tissue proliferates and, for a brief time, macrophages appear. The cuticle layers are produced in order, starting with epicuticular structures such as tricorns and plaques, followed by the biphasic epicuticle, the lamellate pre-ecdysial cuticle and, after ecdysis, the lamellate postecdysial cuticle. Epicuticle is formed in a continuous sheet along the distal epidermal membrane and postecdysial cuticle from fibres formed within the cell body — both features not reported for other arthropods. Immediately prior to ecdysis the epicuticle and pre-ecdysial cuticle are highly corrugated and the epidermis very constricted as the width of the ecdysing gap is increased by the new cuticle components withdrawing slightly beneath the old cuticle. At this time the space between the two cuticles appears devoid of the fluid that once occupied it, although the ecdysial membrane is still apparent. After ecdysis the appearance of the epicuticle changes due to chemical events which make it relatively impermeable. The pre-ecdysial cuticle also changes in appearance at this time due to the physical stress of expansion. Large cuticle precursor vesicles, similar to those of other Crustacea, are particularly associated with postecdysial cuticle production. In addition there are numerous small vesicles associated with pre-ecdysial cuticle formation. The epidermal vacuoles disappear as postecdysial cuticle is produced so that, when it is complete, the epidermis is again a narrow cell layer. Apolysis occurs straight after this and shortly afterwards the cycle recommences. Unlike other arthropods woodlice do not expand to break free of the old cuticle instead they walk free of either half and then expand. Experimental evidence is given which suggests that woodlice do not take in water to achieve this expansion but rather, they appear to employ internal hydrostatic pressure. Using published data from woodlice endocrinological studies and the present work a possible method of hormonal control of the biphasic moult is suggested.

Notizen: Summary The structure of the sound-transmitting apparatus in primitive snakes (Scolecophidia, Henophidia) is reviewed and compared with that of advanced snakes (Caenophidia) and of some fossorial lizards. Assuming a constant course of the chorda tympani, the ophidian stylohyal can be homologized with the intercalary cartilage of lizards while the cartilaginous distal portion of the ophidian stapes represents the internal process. The cladistic significance of the stapes-quadrate-articulation in the Henophidia and Caenophidia is discussed. The Booidea and the Caenophidia show a shift of the stapes-quadrate-articulation which is correlated with changes in the suspensorium as an adaptation to relatively larger prey. However, convergence cannot be ruled out. Dibamus is shown to be the only lizard known so far which approaches the ophidian middle ear structure. Convergence has to be assumed since there is no sign of a stylohyal in Dibamus and since the course of the ramus communicans externus n. facialis cum glossopharyngeo supports the hypothesis that snakes are to be derived from a pre-lacertilian stage of lepidosaurian evolution.

Notizen: Summary The antennal circulatory organs of Melolontha are described for the first time. They consist of small sac-like ampullae located near the base of each antenna and connected to a long non-muscular antennal blood vessel. Small branches of this vessel extend into each lamella of the antennal club and open out distally. The membranous wall of the ampulla provides no contractile structures. An outer adjacent compressor muscle is responsible for the pumping movements of the ampulla and antagonist to it is an obviously elastic connective tissue band. The position of this elastic band causes the uncontracted muscle to be pulled away from the ampulla. As a consequence blood can enter the dilated ampulla through a valvular ostium. The functional type of the antennal circulatory organs in Melolontha is compared to that found in other insects and their histologic structure is interpreted in relation to mechanical and hemodynamical aspects. Furthermore the possible function of the antennal hearts in connection with the spreading of its lamellate antennal club is discussed.

Notizen: Abstract The posterior colon of worker-caste termites accommdates an abundant, heterogeneous population of procaryotic organisms which are retained by attachment to prominent cuticular spines elaborated from the gut wall. The spines extend to nearly one half the diameter of the lumen and are each supported by a specialized root cell in which bundles of parallel microtubules traverse the cytoplasm from the apical to the basal surfaces. Additional epithelial cells are present which show infoldings of the apical plasma membrane and are overlain by cuticle containing deep, vase-shaped pits opening to the gut lumen. It is proposed that the root cells are designed to resist shearing forces transmitted to the base of each spine during contractions of the gut. The cuticular pits may represent sites of permeability to the end products of microbial metabolism.

Notizen: Summary The one-point joint linking the antennula with the carapace in Panulirus argus is described. A strand organ is activated when the antennula is moved in the vertical plane. Its structure, function, and regeneration after severance were investigated. The implications of this system are discussed, starting from the findings that the strand organ counteracts the statocyst (located in the antennula) in such a way that gravity reactions occur only if the body changes its position with respect to gravity.

Notizen: Summary Vascular corrosion casts of the brachial circulation in Octopus were observed under the scanning electron microscope. The angioarchitechture, particularly of the smaller vessels, was revealed with a clarity not previously attained. The casts are very similar in appearance with those obtained from vertebrate tissues, emphasizing the convergent development of the closed system in the two groups, and form a useful basis for further study of vascular structure and function in Octopus.

Notizen: Summary Kraft and ethanol organosolv lignins from Picea abies and Fagus sylvatica were carboxymethylated with bromoacetic acid. Of the total hydroxyl groups in the lignins, 60–70% were carboxymethylated. The reaction led to an increase of the number-average molecular weights. The moisture adsorption of the carboxymethylated products is about one and a half as high as that of the original lignins. There are no remarkable differences between the solubilities of the treated and untreated products.

Notizen: Summary The reactions of quinone methide intermediates during the initial biosynthesis and also the subsequent aging of lignin are reviewed. The reactions during aging should lead to enhanced lignin-carbohydrate bonding and may explain the structural and analytical differences found between DHP and isolated milled wood lignins.

Notizen: Summary Crystalline inclusions were observed in more than 50%, silica in nearly 20% of about 1500 wood specimens representing ±750 species from 40 genera of the laurel family. Both types of inorganic cell deposits are described and classified with regard to composition, habit, size, degree of isolation and location. Their diagnostic value and taxonomic implications on the specific, generic and suprageneric level are discussed with respect to intra as well as extrafamiliar relationships.

Notizen: Summary The longitudinal permeability of Abies grandis wood swollen to varying degree by water vapour sorption has been measured using a non-swelling liquid. The results obtained show that cell wall swelling causes a reversible decrease in permeability in both air dried and solvent exchange dried specimens. Direct microscopic measurements have shown that change in lumen diameter cannot explain the observed effect. Mathematical analysis of the data suggests that the permeability decrease may be due to increase in thickness of bordered pit membrane fibrils resulting from sorption of water.

Notizen: Summary Slow speed wood cutting tests were carried out in which cutting forces were measured as a function of applied tool-work electrical potential. The cutting tool and workpiece were electrically insulated so that there was no current flow. Applied potential had no discernible effect on the cutting forces measured in the cutting of unextracted and extracted wet wood.

Notizen: Summary The acoustic velocities of a wide range of particle boards were determined from measurements of the transit times of wave packets through the materials. Velocities measured along the plane of the board are dependent on the properties of the board's skin layer, and are reasonably well correlated with the board's modulus of elasticity (r=0.73) and modulus of rupture (r=0.65). Velocities measured perpendicular to the plane of the board are not so well correlated with the mechanical properties of the board — the most significant being the Z strength parameter (r=0.56). The results suggest that this form of non destructive testing would be more suited to production line monitoring than to replacing or complementing existing test methods.

Notizen: Summary The study is concerned with the possibility of demonstrating in the transmission electron microscope components such as copper, chromium and arsenic of preservative salts in the wood cell walls using secondary reactions with chemicals. Among the 18 substances tested only 9 showed a substantial positive effect, which was established on the basis of the electron contrast or depositions obtained within the various wall layers. It is suggested that copper is adsorbed onto the matrix substances of the wood cell wall rather than on cellulose.

Notizen: Summary The reduction in hygroscopicity as spruce wood is impregnated with linseed oil may be accounted for using a molecular exclusion model. On the basis of the model, each linseed oil molecule appears to displace 90 water molecules and occupy 6 hydrogen bonding sites in the wood.

Notizen: Summary Kraft pulping is interpreted in chemical terms on the basis of results from extensive qualitative and quantitative model experiments. In essence, the behavior of lignin is explained as a competition between degradation reactions, mainly involving aryl ether cleavage with participation of neighboring groups, and condensation reactions, comprising conjugate addition of carbanions to quinone methide intermediates. The initial phase of technical delignification is tentatively ascribed to the cleavage of α- and β-aryl ether bonds in phenolic lignin units, whereas the cleavage of β-aryl ether bonds in non-phenolic lignin units is considered to be the rate-determining reaction of the bulk phase. The residual phase may possibly be attributed to the rupture of C-C linkages and to aryl ether cleavage without neighboring group participation. Experimental support for these correlations is provided. The interplay of the various lignin reactions, illustrated in a summarizing scheme, explains some known observations in kraft pulping. Attention is drawn to analogies between reactions involved in the degradation of carbohydrates and those reponsible for the degradation of lignin. From the chemical standpoint, therefore, the selectivity of delignification is due to differences in the reactivity of the wood polymers, rather than to differences in the mechanisms of the degradation reactions. This fact explains the limitations of selective delignification.

Notizen: Summary Previous methods for measuring residual longitudinal growth strain distributions in logs are reviewed. An extension is given of Jacobs' method for measuring growth strains which yields residual strain information at many points in the cross section other than along the diametrical plank. Some of the longitudinal growth strain distributions measured using the new method are presented.

Notizen: Summary A method for the derivatization of low molecular weight lignin acidolysis product by reduction-acetylation is described. Borane dimethyl sulfide complex has been used as reducing agent. The derivatives could be analysed by gas chromatography.

Notizen: Summary Geographical location (north/south latitude), social position of trees in a forst stand (dominant, codominant, suppressed) and site quality were investigated as to their effect on tracheid length, proportion of latewood and wood density of black pine indigenous to Greece. Tracheid length was fund greater in the northern location, in dominant trees and at intermediate site qualities. Proportion of latewood was higher in the southern location, in suppressed trees and at intermediate site qualities. Density was higher in the southern location, in codominant trees and at good or intermediate site qualities. Statistically, however, many differences at P = 95 % and all differences at P = 99% are not significant. The present study is based on the sampling of 331 trees, 55 years old and older; the probes were taken only from the 10 outer rings, at breast height. The findings from 6 trees, sampled from pith to bark, present disagreement with the above results.

Notizen: Summary The compound eyes ofPieris brassicae L. have a tiered retina. During light and dark adaptation, ultrastructural changes have been observed throughout the length of the ommatidia in the latero-ventral region of the eyes. These changes have been quantitated by mapping at distinct levels of the ommatidia, and plotted as histograms. Both in visual cells and secondary pigment cells and at the attachment region between crystalline cone and rhabdome such ultrastructural changes have been found to be correlated to the state of adaptation. Distal and proximal photoreceptor cells show different adaptation mechanisms. Whereas the distal cells show a clear pupil mechanism in their distal parts, there is only very little horizontal movement of pigment granules in the proximal cells. In the proximal cells, multivesicular bodies (MVB) are always abundant, while in the distal cells their number is small and increases slightly during light adaptation. In the proximal cells light adaptation causes pigment granules, located in the distal process, to move proximally. Increasing the light intensity from 160 to 1600 μW/cm2 results in more intense migration of pigments. In the secondary pigment cells, a slight but significant distal movement of pigment granules is observed at high light intensity. If continued this condition causes the granules to aggregate in the vicinity of the apical cell membrane, and to move up to the distal inflated extensions of the distal processes formed by these cells. In dark adapted eyes, these processes are nearly devoid of pigment and the pigment granules beneath the apical membrane disperse. In addition to these structural changes, there is a tendency for retinal movements at the attachment from crystalline cone to rhabdome. — The various adaptation mechanisms are not equally well developed in different regions of the compound eye.

Notizen: Summary The lateral and posterior adhesive organs of an undescribed species ofNeodasys can be seen by electron microscopy to have only one gland cell type. This gland has dense spherical secretion granules like secretion granules of the viscid glands of other gastrotrichs, and it extends to the exterior through a tubular extension of the animal's cuticle, the adhesive tubule, as in other gastrotrichs. Each adhesive gland ofNeodasys has a prominent striated rootlet that extends through its full length, attaching at its distal end to a basal-body-like structure at the tip of the gland's neck. Unlike other gastrotrichs,Neodasys has no second gland type that would be equivalent to a releasing gland. The lateral adhesive organs have a sensory cell closely associated with the gland cell but not in direct communication with the lumen of the tubule; it bears a single cilium that projects alongside the adhesive tubule. The posterior adhesive organ has adhesive gland cells whose necks reach to adhesive tubules on toe-like extensions of the animal's body; sensory cells here are not in a one-to-one association with the tubules; a secretory myoepithelial cell extends to the tip of each toe. The adhesive organs ofNeodasys are interpreted as being of a form that would have been found in a common ancestor to the gastrotrichs and from which the duo-gland organs of other gastrotrichs might have been derived.

Notizen: Summary The ultrastructure of the compound eye of the Australian tipulid fly,Ptilogyna spectabilis, is described. The ommatidia are of the acone type. The rhabdom corresponds to the basic dipteran pattern with six outer rhabdomeres from retinular cells 1–6 (R1-6) that surround two tiered central rhabdomeres from R7 and 8. Distally, for about 8 μm, the rhabdom is closed. For the remainder, where the rhabdomere of R8 replaces that of R7, the rhabdom is open, and the rhabdomeres lie in a large central ommatidial extracellular space. In the proximal two thirds of the rhabdom, the central space is partitioned by processes from the retinular cells so that the individual rhabdomeres are contained in ‘pockets’. At night the rhabdom abuts the cone cells, but during the day it migrates some 20 μm proximally and is connected to a narrow (1–2 μm) cone cell tract. This tract is surrounded by two primary pigment cells, which occupy a more lateral position at night and thus act like an iris. Pigment in secondary pigment cells also migrates so as to screen orthodromic light above the rhabdom during the day. Between midday and midnight, the rhabdom changes in length and cross-sectional area as a result of asynchrony of the shedding and synthetic phases of photoreceptor membrane turnover. The effects of these daily adaptive changes on photon capture ability are discussed with regard to the sensitivity of the eye.

Notizen: Summary The sensory palps of the macrodasyoid gastrotrichTetranchyroderma papii contain processes from two types of cell: 22–23 bipolar primary sensory cells and two to three support cells. In the proximal region of the palp each sensory cell contains a short ciliary segment with a basal body and from this ciliary segment a longer distal segment lacking axonemal microtubules extends through the major part of the length of the palp. Each support cell process bears microvilli and contains a conspicuous bundle of microtubules running the entire length of the process. The cell bodies of both cell types are situated in the epidermis of the head region. The palps are interpreted as having a chemosensory function. They are considered to be homologous to the posterior cephalic sensory organ ofTurbanella cornuta, but not the head tentacles ofChordodasys antennatus or nematode amphids.

Notizen: Summary The stylet apparatus ofCarenscoilia bidentata Sopott consists of five hard elements. These are differentiated in a matrix syncytium. During the ontogeny at first microfibrils with a periodic cross-banding arise; then the microfibrils become enveloped by homogenous electron opaque materials. The wall of the developed intracellular hard elements consists of a central layer with microfibrils and outer layers of electron opaque materials. Hard differentiations with a comparable fine structure are only known from other proseriate turbellarians, but not from other platyhelminthes.

Notizen: Summary The gulper Pseudomicrothorax dubius ingests a large volume of filamentous blue-green algae within 1–2 min. Immediately after this rapid phagocytosis, the food is enclosed in a single, extremely large food vacuole, which fills up the ciliate almost entirely. During the following hour this giant food vacuole vesiculates. Finally numerous small vacuoles are present, 1–2 μm in diam. Simultaneously the content of the vacuoles is noticeably condensed. At this time the digestion of the food starts as is indicated by numerous dictyosomes, which now surround the periphery of the food vacuoles. Due to both, the prior vesiculation of the food vacuole and the condensation of the food, the digestive enzymes can act very effectively. After 6–8 hours, when the digestion of the food is finished, numerous empty vacuoles are found. Each is characterized by a highly irregular, convoluted outline. Apparently these vacuoles are eventually recycled to the membrane pool of the cell.

Notizen: Summary The morphology and vascular anatomy of the gills of the Endeavour dogfish,Centrophorus scalpratus, were studied by light microscopic examination of Microfil vascular casts and scanning electron microscopy of vascular corrosion casts and critical point dried tissue. The anatomy of the respiratory vasculature was similar to that described for other elasmobranchs. How-ever, it was noted that approximately one-fifth of the total respiratory exchange area lay within a ventilatory deadspace, thus providing a potential respiratory by-pass shunt pathway. An extensive non-respiratory vascular bed was also present in the gills. In each gill filament there was a series of non-respiratory capillaries arising both from the afferent and efferent sides of the gill circulation (filament corpus cavernosum and efferent filament artery respectively). These capillaries eventually connected to a system of broadly interconnected sinuses in the filament termed the central canal and the afferent and efferent companion vessels. These sinuses connected with a large subepithelial sinus in the gill arch and a pair of large sinuses in the interbranchial septum. It is suggested that the non-respiratory capillaries serve a nutritive function, while the filament, septal and arch sinuses provide a venous and/or lymphatic drainage for the gills. The non-respiratory vascular bed of the gills would not function as a respiratory by-pass shunt pathway.

Notizen: Summary The eye of the slugAthoracophorus bitentaculatus has a singular feature, namely, unusually long receptoral processes, bearing thousands of microvilli, that extend from the distal ends of the type I sensory cells toward the lens. It is concluded that this hypertrophy of the photoreceptoral apparatus is useful to this nocturnal mollusk that nightly ascends trees to forage and returns “home” at dawn to hide from the light of day. Other ultrastructural features of the eye are described, some of which are similar to and some unlike those of other gastropod eyes.

Notizen: Summary The ultrastructure of the compound eyes of 13 amphipod species has been investigated. An amphipod type of compound eye can be characterized by the constellation and consistency of a number of morphological features, most of which are also found in other compound eyes. The amphipod eye falls into four sub-categories (types). The ampeliscid type has a tripartite aberrant lens eye; the lysianassid type has a reduced or no dioptric apparatus and a hypertrophied rhabdom; the hyperid type possesses a large number of ommatidial units with long crystalline cones and dark instead of reflecting accessory pigment; and finally, the gammarid type can be interpreted as a generalized amphipod type. The lysianassid type is adapted to low light intensities and demonstrates convergent development with the compound eyes of other deep-sea crustaceans. The ampeliscid type is more similar to the gammarid type. The type characterization of the amphipod compound eye might well serve as a basis and incentive for functional studies also revealing adaptational mechanisms.

Notizen: Summary The integument of the woodlouse,Oniscus asellus, consists of a two-layered epicuticle, a largely lamellate procuticle — itself divided into two regions (pre-and postecdysial cuticles), and the epidermis. At the initiation of new cuticle production the epidermal cells become vacuolated and retract away from the cuticle. Apolysis occurs immediately after the cessation of postecdysial cuticle production. The formation of the epicuticle is unique among the arthropods since material aggregates along the distal epidermal membrane. By indenting, doubling back on itself, and incorporating septa, the epicuticle forms surface structures such as plaques and tricorns. The innervation, and so the receptive function of the tricorns is confirmed, but since there is no connection between the old and new receptors during premoult, sensory information from these exoreceptors must be severely curtailed. This may explain the biphasic moult in all isopods since it ensures that only half the body experiences this sensory deprivation at any one time. In terrestrial species there is the additional advantage of restricting the area of permeable new cuticle. The frequency of moulting may be due to the need to renew disrupted receptor surfaces. Tricorns do not appear to be the mechanoreceptors involved in the marked thigmotactic response of woodlice since they do not have the typical internal structure of such receptors; rather, the dendrite —which extends into the lumen of the tricorn —is protected from deformation by the previously unreported combination of a dendritic sheath and a cuticular tube. The modality of tricorns is possibly one of hygro-perception. One of the behavioural responses of woodlice to desiccation is aggregation. The numerical distribution of tricorns over the body surface is admirably suited to assist in the formation and maintenance of such aggregates during desiccation and to their observed dispersal when the relative humidity rises.

Notizen: Summary This is the first paper of a series dealing with the new interstitial, monotypic family Lobatocerebridae. The single genusLobatocerebrum is described as a turbellariomorph taxon in the annelid line of evolution. The male genital system, the protonephridial system, the body wall and the anus-hindgut system reveal the most important characteristics for the determination of its phylogenetic position. Although presently the group can not be clearly aligned with any of the classes within the Annelida, the new family is provisionally included into the Oligochaeta, until further, yet undescribed species of this group will reveal better the within-group characterconsistency. Because of the high degree of superficial similarities to the Turbellaria (acoelomate body cavity, complete ciliation, lack of signs of segmentation, special features of the foregut, arrangement of reproductive organs) this paper argues that the Lobatocerebridae may become an important example for trying to understand the origin and evolution of acoelomate flatworms from coelomate ancestors.

Notizen: Summary The integument ofCampodea- species, both endogenous and subterranean, shows dermal glands in males and females. Each of them consists of 3 cells: one secretory, one intermediary and one reservoir cell. The secretory product passes through a sieve located at the lower part of the reservoir.

Notizen: Summary The vascular anatomy of the lateral musculature of the flatheadPlatycephalus bassensis, was studied by scanning electron microscopy of corrosion casts. Arteries and veins showed an alternating pattern in neighbouring vertebral segments. The red muscle was supplied by five major branches of the intermuscular artery, and the white muscle by infrequent branches of the intermuscular artery, dorsal segmental artery and ventral segmental artery. Venous drainage of the red and white muscles broadly mimicked the arterial supply. The functional unit of the trunk vasculature can be considered as an artery, a vein and connecting fine blood vessels. There appear to be 2 over-lapping types leading to alternating clockwise and counter-clockwise flows of blood. Small satellite vessels were observed running parallel to most of the larger blood vessels. No anatomical A-V shunt vessels, or series vascular connections between the red and white muscle, were observed. The irregular, alternating adult system is postulated to have developed from an earlier system showing strict bilateral symmetry and equal arterial and venous development in each vertebral segment.

Notizen: Abstract Crystalline styles are present in nearly all bivalve mollusks, and are known to undergo cyclic changes in size and/or occurrence in many species. A few gastropod species are known to possess styles, but such cycles as may exist are unknown or not well documented. Results reported here show that Ilyanassa obsoleta (Say) in a sandflat population lose and regain their crystalline styles each day. Styles were consistently low in frequency just after dawn. The presence of this kind of rhythm in a deposit-feeding gastropod has not previously been noted. It is suggested that this cycle may have played a key role in the evolution of this widespread and numerically abundant species.

Notizen: Abstract Acute single exposures to the water-soluble fraction (WSF) of a No. 2 fuel oil influences several biochemical parameters in juveniles of Mugil cephalus Linnaeus. Plasma cortisol and glucose concentrations were measured at 1 and 3 h after exposure to 1, 5, 10 or 20% WSF. No elevation of plasma cortisol or glucose levels occurred in fish exposed to the lowest concentration of oil, whereas a dose-response relationship was observed at higher doses. The dynamics of plasma corticosteroid, glucose and cholesterol concentrations and osmolality as well as accumulation of naphthalenes in the fish tissues were monitored during exposure to 20% WSF. Circulating cortisol concentrations rose rapidly to 5 times normal values 1h after exposure to oil and subsequently declined to control levels 6 h after oil addition. A smaller secondary rise occurred at 12 h, but cortisol had returned to basal levels 12 h later. In contrast, plasma glucose, cholesterol and osmolality rose more slowly to reach maximum values between 3 and 4 h after oil addition. By 24 h plasma cholesterol and osmolality had returned to normal values whereas the hyperglycemia persisted. However, 72 h after the addition of WSF all biochemical parameters had returned to control levels. At this time considerable accumulation of total naphthalenes had occurred in several fish tissues, whilst the concentration of total naphthalenes in the exposure tanks had declined to background levels. When freshly prepared 20% WSF was added to the exposure tanks during this period, all biochemical parameters were again elevated. The results suggest that the volatile components of fuel oil in the water trigger the biochemical changes described in a dosedependent manner. The possible ecological significance of these changes and the potential use of these parameters as sublethal indicators of environmental contamination are discussed.

Notizen: Abstract Dry weight levels of the red alga Hypnea musciformis (Wulfen) Lamouroux from Atlantic and Gulf of Mexico coastal sites in florida, USA were lowest in the late winter and early spring, increasing through the summer and highest in the fall. There was a two-month lag in the Gulf coast population's dry weight pattern, indicating differing growth patterns. Chlorophyll a, phycoerythrin and phycoerythrin/chlorophyll a ratios were highest in the winter and lowest in the summer for both populations. Total pigment levels for H. musciformis from the Atlantic coast site were significantly greater than those of the Gulf coast. Protein and carbohydrate percentages were inversely related in both populations, with carbohydrate levels highest in summer and protein levels highest in winter. The Gulf coast population contained significantly more protein than the Atlantic coast plants. Carrageenan levels were highest in spring and lowest in fall, the Atlantic coast population generally had higher levels than the Gulf coast population. The differences in seasonal patterns and levels of the chemical constituents were reflected by distinct morphological characteristics for each population. The Atlantic coast population was larger, darker, more coarse in texture and possessed more crozier branch tips than the Gulf coast plants. These distinctions represent acclimitization responses that relate to habitat differences.

Notizen: Abstract Respiration rates of Hypnea musciformis (Wulfen) Lamouroux in Florida, USA, generally increased with increased temperature. Gulf coast H. musciformis respired at significantly higher rates than the Atlantic coast population, which exhibited a region of temperature independence between 24°–32°C. Respiration rates were highest in the fall and winter, during the periods of rapid growth. Respiration rates were lowest in the summer indicating a period of storage and low metabolism. Photosynthetic responses to various levels of light and temperature indicated that the Gulf coast population was more tolerant to high light intensities than the Atlantic coast population. Maximum photosynthetic responses for both populations occurred between 24° and 32°C which corresponds to the shallow slope region of the respiration-temperature curves. The results indicate that water temperature rather than light intensity is a significant factor in modifying seasonal photosynthetic capacities. The greatest seasonal variation in photosynthetic responses occurred at the light-temperature levels of highest responses while little seasonal variation was demonstrated at tolerance limits.

Notizen: Abstract The concentrations of cadmium in 428 samples of the sea-skater Halobates micans from 57 locations in the central and south Atlantic Ocean ranged from 1.7 to 122 μg Cd g-1 dry wt. The concentrations in females, males and nymphs were not significantly different. The data suggest that the cadmium concentrations in these insects are somehow related to surface currents. The highest values (50 to 70 μg g-1, maximum value 122 μg g-1) were recorded from the South Equatorial Current region; intermediate values (10 to 20 μg g-1) from the Equatorial Counter Current and the North Equatorial Current; and relatively low concentrations (〉10 μg g-1) from the Canary Current in the north and the Benguela Current in the south. A remarkable feature of these data lies in the fact that they reveal areas of high Cd content which correspond closely with those indicated by data obtained by Bull et al. (1977) from a different set of samples, analyzed by different methods and obtained in different years.

Notizen: Abstract The demography of Pelvetia fastigiata was studied from 1973 through 1977 in the intertidal zone near La Jolla, California, USA. Populations were usually small and relatively stable as new recruits replaced older individuals that were lost; however, in 1977 high recruitment substantially increased total abundances. The survivorship of recruits was similar regardless of the season or year of recruitment. Mortality rates decreased with age, and the mean life expectancy continued to increase for at least 1 yr. Losses of juveniles were high; 50% lived 80 d and only 9% survived to the age of first reproduction (about 1.5 yr). Plants present at the start of the study had higher survivorship rates than new recruits, 19 and 7%, respectively, living more than 3 yr. Individuals within aggregations of large plants lived longer than most dispersed individuals, and aggregations remained intact throughout the study in spite of low recruitment. Established individuals had low mortality rates and populations probably relied on these persistent individuals for reproduction.

Notizen: Abstract Four colonies of Acropora formosa were incubate with Na2 14CO3 for separate 2 h periods within a 24 h period, and then returned to the reef from which they were collected. Terminal branches were collected at intervals over the following 5 d and analysed for radioactivity associated with the skeleton and certain organic pools. Colonies incubated at night showed little or no loss of fixed radioactivity during the 5 d on the reef. However, 50–60% of photosynthetically-fixed 14C was lost from the terminal branches during the first 40 h on the reef. This loss of radioactivity probably resulted from release of mucus and dissolved organic carbon from the coral tissues. Most of the loss of photosynthetically-fixed 14C was due to decrease in the radioactivity of lipids (80% of the total 14C loss) and methanol-water soluble compounds. Determination of any sequencing in metabolic compartments was made difficult by the rapidity with which 14C dissappeared from most of the metabolic pools measured. 14C was incorporated into the skeleton throughout the 5 d on the reef, although the rate of incorporation was very low in colonies which had been incubated with Na2 14CO3 at night.

Notizen: Abstract The effect of temperature on feeding, duration of emergence and movement by the crab Scylla serrata (Forskal) was measured under laboratory conditions using infrared time-lapse photography. Little difference was found between experiments carried out at 25° and 20°C. All parameters measured declined at 16°C. At 12°C emergence time and movement were 24 and 33% respectively of the level at 25°C. At 25°C, 65% of crabs fed, but none did so at 12°C. No statistically significant difference was found between male and female crabs in the parameters measured.

Notizen: Abstract The possible interactive effect of the chlorides of copper and mercury on the euryhaline amphipod Gammarus duebeni in 100% sea water was examined using the following indices: (i) 96 h LC50 values, (ii) urine production rates and (iii) degree of mercury accumulation. Both (a) the interaction of the chlorides of mercury and copper together in solution and (b) the influence of cupric chloride pre-treatment of individuals prior to exposure to mercuric chloride were investigated. Presence of a sublethal level of cupric chloride protected G. duebeni against the toxic action of mercuric chloride. Cupric chloride pretreatment was not so effective. The nature of the interaction between mercury and copper is discussed.

Notizen: Abstract The nature of protein catabolism in a wide range of species of midwater zooplankton was investigated. The weight-specific ammonia excretion rates (μg NH3−N g−1 dry wt h−1, y) decline exponentially with minimum depth of occurreece (MDO, x), y=163.4 x−0.479±0.212 (95%ci) (CI=confidence interval), when temperature is held constant. The change in ammonia excretion can be partially explained by the decrease in percent protein (%P) with MDO, %P=80.17 MDO−0.148±0.122 (95%ci) The atomic O:N ratio of freshly caught zooplankters ranged from 9.1 to 91, with most measurements between 9 and 25. Detailed studies were carried out on the response of one of the species studied (Gnathophausia ingens) to starvation (28 d). After 14 d of starvation the average ammonia excretion rate declined by more than 75% to less than 1 μg NH3−N g−1 wet wt h−1, although the average oxygen consumption declined by only 13% within the first 7 d of starvation and then remained stable. This differential response of oxygen consumption and ammonia excretion to starvation resulted in an increase in the average O:N ratio of starved animals from an initial 33 to 165 after 21 d. The average O:N ratios of fed mysids remained below 38 during the experiment. G. ingens maintains a relatively uniform metabolic rate during starvation by relying more heavily on its large lipid stores than when being fed.

Notizen: Abstract Results from the Continuous Plankton Recorder (CPR) survey for 1966 and 1967 are used to describe seasonal changes in abundance, size and aspects of the population structure of Thysanoessa inermis (Krøyer) and T. raschi (M. Sars) at a depth of 10 m in the North Sea and in American coastal waters from the Grand Banks to the Gulf of Maine. Production and dry weight were estimated from these data. Two year-groups were usually present in the breeding population, the proportion surviving into a second year being higher in American waters than in the North Sea. Annual production for each species was within the range 0.69 to 4.66 mg m-3 and the ratio between production and biomass (P:B) was between 1.3 and 4.2; values outside these ranges were obtained only for American coastal waters in 1967, when the frequency of sampling was low.

Notizen: Abstract The effects of body-size and temperature on moulting frequency of the shrimp Lysmata seticaudata Risso were examined under controlled laboratory conditions. Shrimp ranging in weight from approximately 0.4 to 1.14 g and maintained at 17°C exhibited intermoult periods of similar duration (≈20 d). On the other hand, small individuals (0.23 g) held at the same temperature moulted on the average every 14.5 d. Over a temperature range from 8° to 20°C mean intermoult periods were inversely and linearly related to temperature; an increase of 1 C0 resulted in a decrease in the intermoult period of approximately 1.5 d. Although temperature acted to regulate the intermoult period of each shrimp in increments of whole days, it had little effect on the time of moulting within any 24 h period, since moulting occurred more than 93% of the time between 18.00 and 08.00 hrs. The night-time moulting pattern also tended to be most pronounced at lower temperatures (8° and 13°C) and in larger individuals. Possible factors controlling this phenomenon and its occurrence in other crustacean species are discussed.

Notizen: Abstract The survival of Orchestia chiliensis (Milne Edwards, 1840) was investigated at salinities between 0.3 and 68‰ and constant or 10 C° cyclic temperatures between 5° and 25° C. Mortality increased with age, temperature and at salinity extremes. Small individuals show little seasonal acclimatisation apart from increased thermal tolerance at the highest exposure temperature. Larger individuals show a lateral shift in the mortality curve to the right in summer, giving increased survival at most salinities. Salinity had less effect on amphipods in cyclic regimes and survival was similar in 5° to 15° C and 10° to 20° C cycles. Mortality of larger individuals was higher in the 15° to 25° C cycle, but seasonal acclimatisation gave increased resistance at all fluctuating temperatures during the summer. Mortality in cyclic temperatures was higher than at similar constant temperatures. O. chiliensis does not actively evade immersion and diel temperature changes of 10 C° represent an important stress factor. This would affect all life stages and influence field populations both in the winter and the summer.

Notizen: Abstract The stomach of a 10.2 m (34 ft) male sperm whale which became stranded at Rio Grande do Sul near Rio Grande, Brazil contained 227 upper cephalopod beaks and 255 lower cephalopod beaks. The lower beaks were identified and measured. Beaks of 14 species belonging to 9 families are present. Lower, rostral lengths are compared with those of the same species collected from stomachs of whales killed off South Africa and in the Antarctic. Estimates of the weight of flesh of the various species represented by beaks are made. Two ommastrephid species are estimated to contribute 33.1% of the weight of flesh represented by beaks while the octopoteuthids contribute 28.3% and the Onychoteuthids 18.5%. Three Antarctic species in the stomach show that the whale had migrated from south of Lat. 40°S prior to being caught and had not eaten much food during the journey which would probably have taken him more than 5 d.

Notizen: Abstract A method of measuring the relative scouring (wave action plus type and concentration of suspended solids) of intertidal areas, based on the weight loss of cement blocks anchored to the substrate but able to move in a hemisphere and undergo abrasion, was developed and tested at a number of sites on the west coast of Vancouver Island, British Columbia over a period of 8 months (September to May). The results suggest that it may be a useful and simple method which takes into account both the intensity and duration aspects of exposure, particularly in widely spaced, relatively inaccessible areas.

Notizen: Abstract Of 379 cephalopod beaks sampled from stomachs of 20 sperm whales caught to the west of Vancouver Island, Canada, 152 beaks were sorted and measured. Thirteen types of beak were identified as belonging to eleven families. The most numerous species represented are Berryteuthis magister and Moroteuthis robusta comprising 28.9 and 24.3% respectively. These species were estimated to comprise 17.6 and 61.9% respectively of the weight of flesh represented by beaks.

Notizen: Abstract In two temperate reef fish, Pseudolabrus celidotus (Bloch and Schneider) and Tripterygion varium (Bloch and Schneider) studied near Leigh, New Zealand, most spawning activity was concentrated during the first 2 months of spawning seasons which lasted about 5 months. In P. celidotus, maturation and spawning of first-year females (0+) was delayed with respect to older (≥1+yr) females. Within the 0+ age class, the minimum size of maturation declined as the spawning season proceeded. However, in all females of T. varium, ripening and spawning took place over the same time ranges. Observations on the seasonal patterns of female aggression suggested that larger female P. celidotus were socially inhibiting the maturation of small females. The level of interaction was high compared to that in T. varium, and reached a peak over the onset of the spawning season. This hypothesis was tested by the removal of larger (≥1+yr) female P. celidotus from a field population. The remaining 0+ females increased in ovary weight and matured earlier than those in an undisturbed area. We argue from this experiment that it is of advantage for P. celidotus females to spawn early in the season and of advantage to inhibit other females from doing so. Two possible reasons are suggested, the first applying to sexchanging species such as P. celidotus, the second to temperate-water fishes in general.

Notizen: Abstract The effect of light intensity and oxygen concentration on the growth of an estuarine diatom was investigated. Differences between rates of cell division and net carbon fixation were found to be dependent upon light intensity and oxygen concentration. Under conditions favoring large differences between cell division and net carbon fixation cultures of Thalassiosira pseudonana clone 3H depart from exponential and enter stationary phase at low cell concentrations. It is suggested that single cell algae may not be able to balance maintenance, growth, and division outside a fairly narrow range of environmental conditions.

Notizen: Abstract The nekton of tidal creeks was studied at 17 sampling localities from September 1977 through August 1978, in the Cape Fear River estuary, North Carolina, USA. Prior to these dates, collections were made at 9 stations beginning in January 1977; these data were used to supplement conclusions drawn from the larger effort. Species recruited from the ocean utilized marsh habitats only temporarily and dominated the catches with over 70% of the total abundance. Their distribution was influenced by salinity gradients and to a lesser extent by substrate characteristics. In addition, temporal habitat partitioning with associated size differences of related species played an important role in structuring marsh nekton communities. A clearly defined ecotone was associated with the mesohaline-polyhaline transition zone, in slainities between 14 and 21‰ S. Numerous marine stenohaline forms were restricted to salinities above 16‰ S, thus increasing species richness in high salinity marshes. Despite differences in freshwater flows in 1977 and 1978, major features of the various marsh communities (species associations and relative abundances) exhibited little change throughout the Cape Fear estuary, indicating that these communities were relatively persistent in time. Standing crops for ocean-spawned species at the end of the growing season indicated that considerable annual export in the form of living biomass of fish and shellfish takes place from the marshes. Since most individuals of these species return to the ocean in the fall, an important energy link between the marshes and nearshore marine environment is demonstrated.

Notizen: Abstract This study examines the accumulation of 74As-arsenic in the seaweeds Fucus spiralis (L.) and Ascophyllum nodosum (L.) collected from Restronguet Creek in southwest England during 1978. Also, the influence of environmental factors (valence state of arsenic, pH, salinity, temperature, phosphate concentration) and metabolic inhibitors on the uptake of arsenic by F. spiralis is examined. Most of the arsenic in the seaweeds was non-exchangeable with labelled arsenic in the medium. The accumulation of 74As reached a steady state in 1 to 8 d, depending on the species and external arsenic concentration. At steady state the accumulated arsenic is proportional to external arsenate concentration. F. spiralis accumulated 4 times more arsenate than arsenite. The short-term uptake of arsenic increased in proportion to the external arsenic concentration up to a level of 1000 μg l-1; it then remained constant at higher levels of arsenic. Arsenic uptake increased in direct proportion to increasing temperature. Variation of pH or salinity had no effect on arsenic incorporation. The accumulation of arsenic occurred only in living tissue and was inhibited by KCN in a concentration-dependent manner. The uptake of arsenic by F. spiralis in the presence of photo-synthetic inhibitors (DCMU or CMU) or in the dark was greater than in the light controls. Thus, it was concluded that energy is required for arsenic uptake and this is derived from respiration rather than photosynthesis. There was no evidence for a common mechanism of phosphate and arsenate uptake by macroalgae, although high concentrations of phosphate (40 to 400 μM) initially inhibited arsenate uptake.

Notizen: Abstract The mechanism, and factors influencing the process of arsenic accumulation and elimination in a food chain [Fucus spiralis (L.) → Littorina littoralis (L.) → Nucella lapillus (L.)] were examined using the radioisotope 74As. Organisms were collected during 1978 from the estuary of Restronguet. Creek in southwest England. Arsenate uptake by L. littoralis increased linearly with increasing external arsenate concentration up to ca. 500 μg 1-1 but was independent at higher arsenate concentrations. Arsenic uptake by L. littoralis was suppressed by metabolic inhibition (potassium cyanide) and lowered salinity. At 26°C, arsenic uptake was twice that at 10°C. L. littoralis accumulated 1o times more arsenic from solution than N. lapillus. Approximately 91% of 74As accumulated from water by L. littoralis was found in the soft tissues, especially the digestive gland and gonads, but in N. lapillus 85% was associated with the shell. Arsenate uptake was twice that of arsenite in L. littoralis. Phosphate at normal environmental levels (2.4 μM) did not influence the accumulation of arsenic by L. littoralis, although concentration-dependent inhibition of arsenic uptake was found between 8 and 17 μM. Compared with macroalgae, the marine snails exhibit a much greater ability for eliminating arsenic. In L. littoralis the elimination of 74As absorbed from sea water occurred in three stages, each contining equal amounts of the initial 74As pool, with biological half-lives of 4, 13 and 47 d. A biphasic pattern of elimination was found for food-labelled snails (L. littoralis and N. lapillus). The rapid compartment, contributing a third of the arsenic, had a half-life of 4 d, while that of the slow compartment was 12 to 13 d. Fed snails eliminated arsenic more rapidly and extensively than starved individuals. All arsenic in the tissues of the snails studied was available for exchange with that in the environment. The diet is by far the major source of arsenic in L. littoralis and N. lapillus, which appear equally efficient at assimilating arsenic from food.

Notizen: Abstract An investigation was made into the possible causes for the decline of physiological activities in Acetes sibogae australis Colefax and Acartia australis Farran during their maintenance for a period of 2 d following capture. Physiological activities comprising respiration, electron transport system (ETS) activity and excretion of ammonia and phosphate, and the biochemical components protein, RNA, ATP and adenylate energy charge (EC) were measured. Excluding fluctuation in the ammonia excretion rate, physiological rates and biochemical components decreased on an individual basis with time after capture for both species for this period. These decreases were generally moderated if expressed on a protein basis. Notwithstanding these changes, the adenylate EC of both species was constant at the normal level. From the results of stable EC and other physiological and biochemical consequences, it was concluded that food shortage rather than capture stress was the major factor contributing to decreases in the various physiological and biochemical properties of the two zooplankton species studied.

Notizen: Abstract The present study investigates the importance of foam in nearshore waters on the west coast of the Cape Peninsula (South Africa) as a possible food resource for consumer organisms. A bacterial density of 3.45x109 cells ml-1 foam suspension was recorded. Calorific values of up to 15.39 kJ g-1 ash-free dry weight were noted, and a biochemical analysis of the drained foam suspension gave a composition of 22.85% protein, 10.76% lipid and 3.07% carbohydrates. Field data showed a correlation between peaks of phytoplankton up to 510 mg C m-3 water temperatures and days of intense foam formation during periods of strong onshore winds. Experimental foam formation in the laboratory indicates that kelp mucilage and phytoplankton contain surface-active agents. An additional feature of kelp mucilage is its capability to improve foam stability. The comparison of the chemical composition of 12 and 120 h-old foam suspension indicates a loss of easily metabolizable components such as trichloroacetic-acid precipitated protein and neutral lipid with time. It is hypothesised that the losses are due to utilisation of these components by consumers.

Notizen: Abstract Spatial and temporal feeding patterns (determined from an index of gut fullness) are described for 10 typical species of calanoid copepods collected from the North Pacific central gyre (September 1968 to June 1977), an area where the zooplankton is food limited and there were a-priori reasons to suspect that feeding and competition for food were important in regulating zooplankton community structure. Over 100 samples from 11 cruises to the eastern part of the gyre were examined, and patterns of gut fullness were related to environmental variables and the copepod species structure. The copepods studied all tended to be omnivores and food generalists. Males had lower indices of gut fullness than females but both males and females of a species had similar spatial and temporal feeding patterns. Guts were usually fuller at night than during the day, even in nonmigrating species; however, within nighttime depth distributions, no depths were preferred for feeding. There were also differences between species in mean gut fullness, but different species tended to have similar spatial and temporal feeding patterns. There was considerable spatial variability, and locales could be identified in which most species had higher indices of gut fullness. The copepods were not necessarily more abundant in these locales, nor did these tend to be areas of above average chlorophyll concentration. These patterns were consistent with relatively nonselective feeding, and there was no evidence that these species separate their niches by feeding at differing places or times.

Notizen: Abstract The polychaete Nereis diversicolor O. F. Müller was exposed to marine sediments which had been contaminated with 55Fe either through the testing of nuclear devices or by the release of liquid waste effluent from a nuclear fuel reprocessing plant. The amount of 55Fe taken up reached a concentration in the worms about 6% of the concentration in both types of sediment. Bioavailability of 55Fe was shown to depend on its concentration in sediment and not on sediment type, stable iron concentration, or the source of contamination. N. diversicolor may not extract from sediment the same fraction of 55Fe as does 0.1N HCl and caution should be exercised in using such measurements to represent the bioavailable fraction.

Notizen: Abstract Radiotracers were used to study processes controlling the accumulation and elimination of vanadium in the Mediterranean mussel Mytilus galloprovincialis. Vanadium uptake rates varied inversely with both salinity and vanadium concentration in water, but were independent of temperature. After a 3 wk exposure to 48V, the highest concentration factors were found in the byssus (≈1900) with much lower values computed for shell (≈ 70) and soft tissues (≈5). More than 90% of the total 48V accumulated was fixed to shell, suggesting that uptake is primarily a result of surface sorption processes. Much of the vanadium in shell was firmly bound to the periostracum and was not easily removed by acid leaching. Food-chain experiments indicated that the assimilation coefficient for ingested vanadium is low (≈7%) and that the assimilated fraction is rapidly excreted from the mussel. These findings coupled with knowledge of in situ and experimentally-derived vanadium concentration-factors have allowed a preliminary assessment of the relative importance of the food and water pathways in the contamination of mussels under conditions of acute and chronic exposure. Contaminated mussels transferred to clean sea water lost 48V at rates that depended upon temperature but were largely unaffected by either salinity or by vanadium levels in mussel tissues. Total vanadium depuration was slow and was governed by loss from a slowly-exchanging compartment with a characteristic half-time of about 100 d. Individual mussel tissues were analyzed for stable vanadium and the possibility of using these tissues, particularly the byssus, as bioindicators of ambient vanadium levels in the marine environment is also discussed.

Notizen: Abstract Gluconeogenesis in fishes has been demonstrated in whole animals and liver preparations. However, at present, the relative physiological importance of possible substrates such as lactate, pyruvate and amino-acids or the precise sites of gluconeogenesis are unclear. In mammals, gluconeogenesis takes place in the liver and kidney, and the same could occur in fishes although it has been proposed that fish red muscle is also capable of reconverting lactate (derived from white muscle) to glucose. In this present study, the activities of 3 key glycolytic (hexokinase, phosphofructokinase and pyruvate kinase) and 2 key gluconeogenic (fructose diphosphatase and phosphoenolpyruvate carboxykinase) enzymes were investigated in tissues of the rainbow trout Salmo gairdneri, the cod Gadus morhua, and the plaice Pleuronectes platessa in order to elucidate the relative glycolytic/gluconeogenic capacities of the individual fish tissues. The glycolytic enzymes were found in all tissues, the relative potential being skeletal muscle〉heart, brain 〉kidney, gills〉liver. The gluconeogenic enzymes were not present in all tissues, and were mainly concentrated in the liver and kidney. Hence the results indicate that the liver, and to a lesser degree, the kidney are the major sites of gluconeogenesis in fishes, and that the process is unlikely to occur in skeletal muscle.

Notizen: Abstract A study of the calcareous tube-building polychaete Hydroides dianthus (Verrill) in a temperate estuary (Delaware Bay, USA) revealed an assemblage that was strongly associated with the serpulid. This polychaete species provided numerous microhabitats by means of its tubes and sediment enriched with tube fragments. Quantitative associations for winter and summer tube heads showed that 17 and 12 species, respectively, were statistically dependent on H. dianthus. There were significant associations between number of species, number of individuals, mean number of animals, standard deviation, the size of the tube clump for both seasons (winter and summer), and for scaled standard deviation (SDN) and species diversity (H) during the winter. Successional development of the serpulid assemblage starts with the settling of H. dianthus, progresses through growth, maturation, mortality, and the interaction of associates and predators, resulting in a highly diverse benthic assemblage in this temperate estuary.

Notizen: Abstract A study of gonadal state in 39 small specimens of Arctica islandica Linné collected in April 1976 from the Middle Atlantic shelf of North America suggests that sexual maturity is reached at a later age than has been reported for other shelf bivalves. Eight of the specimens had gonads in the undifferentiated state. On the basis of annual internal growth banding in the shells of these immature specimens, age ranged between 4 and 14 years. Average age was 9.38 years (standard deviation, s,= 3.54). Shell length ranged from 24 to 47 mm (average 38.85 mm, s=9.25). Differentiated gonads were found in specimens as young as 6 years. Age of maturity shows a wide range and may be dependent upon growth rate and locality.

Notizen: Abstract The community of epibenthic organisms growing on the roots of the red mangrove Rizophora mangle was studied from March 1976 to September 1977, at a site 100 km east of Caracas, Venezuela. Recruitment was relatively constant and low in intensity for most species. Asbestos panels submerged in March–April 1976 and November 1976 were similar in species composition by September 1977; species composition of panels submerged in March–April 1976 did not change greatly between November 1976 and September 1977. There was little change in the mean species composition on ca. 120 roots during the 18 month study period. The major feature of the community was the large differences in species composition among roots. Even species which were rare in the community as a whole were common on some roots. I ascribe these differences to chance resulting from the low recruitment rate of most species and the low rate of supply of new roots (≅8% yr-1). Once present on a given root, species seem to live for many years and resist the invasion of most other larvae. The initial differences in species composition among roots persists and the overall community does not change greatly with time. Predation had little effect on community development.

Notizen: Abstract The turnover rate constants (k) of alanine in coastal marine sediments were measured using 3H-and 14C-alanine in tracer amounts (less than in situ concentrations of alanine in the porewater). After incubation 14C-label was recovered in free dissolved alanine, adsorbed alanine, volatile fatty acids and carbon dioxide pools. Alanine left the free dissolved pool by two processes: 1) adsorption (k=0.06 min-1) and 2) biological uptake (k=0.16 min-1). Adsorption of alanine was deduced from the persistence of 14C-alanine, which was slowly metabolized after an initial rapid rate of degradation. Adsorption was confirmed in biologically inactivated sediments. The adsorbed 14C-alanine was only partially exchanged by the addition of excess non-labelled alanine, indicating the existence of at least 2 different adsorbed pools. The rates of adsorption and desorption were equal, but the k-values were different, indicating that the adsorbed pool was 2500 fold greater than the free pool. From the biological turnover rate constant (0.16 min-1), the mineralization percentage (80%) and the concentration of alanine (800 nmol l-1 of porewater) a mineralization rate in the sediment of 75 nmol cm-3 d-1 was determined. This was in excess of the measured total NH 4 + production. It is concluded that much of the dissolved alanine (800 nm) was biologically unavailable and a more realistic free dissolved pool would be ∼10 nM.

Notizen: Abstract Tagged black-and-yellow rockfish Sebastes chrysomelas and gopher rockfish S. carnatus were observed in situ for 1 yr at 3 study sites off California, USA in order to determine the nature of their home ranges and territories. Three basic patterns of space use were identified: (1) a shelter hole located within a larger area of activity (in which the fish presumably fed, since its size increased with size of fish and decreased with prey density); (2) discontinuous home ranges, in which the shelter holes and feeding areas were separte; and (3) dispersed home ranges with little or no exclusive area. Fish in the first category were regarded as territorial, since their home ranges were defended and relatively exclusive. Because individuals did not patrol borders, however, territories often overlapped at their peripheries. In addition, some territory holders appeared to tolerate the sheltering of other fish within their territories, as long as these intruders left the territory during periods of activity. Some fish with discontinuous home ranges (“commuters”) may have been territorial, but others may have been forced to occupy suboptimal feeding areas. Fish in the third category (“floaters”) were regarded as nonterritorial; their activities were apparently limited to areas where they could escape the aggression of territory holders. The varying patterns appeared to develop through defense and accommodation during the turnover of individuals, with each fish securing shelter and feeding areas as these became available.

Notizen: Abstract Egg production by Acartia clausi hudsonica ceases at low concentrations of Isochrysis galbana as food and at high levels reaches a maximum that increases with temperatures in the natural range. This increase parallels the rate of production of fecal pellets. Females without males can produce about 400 eggs before entering a generally short postreproductive period. Weight increments between copepodite stages are exponential and, assuming isochronal durations of stages and that development time of older stages is the same mutiple of embryonic duration at all temperatures, a temperature-dependent rate is estimated for pre-adult growth. We demonstrate that this growth rate also predicts the observed maximal rate of egg production by the nongrowing adult females. Published data for other copepod species (except Pseudocalanus) are inadequate for wider testing of this hypothesis, but available data do suggest that no such simple rule governs total output of eggs by females of different species.

Notizen: Abstract The in situ decomposition rate of urea was measured using 14C-labelled urea at 3 areas in the North Pacific Ocean: Sagami Bay on the southern coast of central Japan, the northwestern Pacific central waters and the subarctic Pacific waters. The mean values of the decomposition rates of urea in surface waters of these areas were 44.5, 1.51 and 1.32 μ mol urea m-3 d-1, respectively. These rates decreased with depth. High rates of urea carbon incorporation into particulate matter and the CO2 liberation from urea carbon into seawater were obtained in light bottles in the euphotic zone, while low rates were found in dark bottles. The turnover rates of urea in the 3 areas were calculated respectively as 12, 113 and 110 d at the surface, and the values increased with depth.

Notizen: Abstract The responses of the post-embryonic stages of Corophium volutator (Pallas) and C. arenarium Crawford to the combined effects of salinity and temperature show that gravid females have a wider tolerance than nongravid adult females which in turn are more tolerant than adult males. C. volutator is more tolerant of low salinity (2 to 10‰) than C. arenarium, but the latter is more tolerant of salinities above 45‰. The embryos of C. volutator develop normally and hatch at lower salinities and temperatures than those of C. arenarium, in which successful development was recorded at higher temperatures. Females undergoing a pre-copulatory moult failed to lay eggs below salinities of 3‰ (C. volutator) and 10‰ (C. arenarium), but in both species the lowest salinity at which all females moulted and laid eggs was 20‰. The results are discussed in relation to the distribution of both species.

Notizen: Abstract The digestive processes of Mercenaria mercenaria (Linn.) were studied in a natural subtidal population. Hourly sampling of 4 to 5 quahogs was conducted over one 25 h period in August, 1978, at Woods Hole, Ma., USA. Crystalline style length did not vary significantly with time, tide, particulate C, N or suspended material in the water. Changes in secretory activity of the style sac epithelium were not evident from histological sections. Based on cellular morphological differences, digestive tubules were individually classified into one of 4 categories, indicative of the state of intracellular digestion within the digestive cells. All 4 tubule types were present in individuals from each sample hour, signifying that intracellular digestion occurs continually within the digestive gland. A 3 h time lag is evident between times of peak C, N or suspended materials and apparent peak levels of absorptive (Type II) tubules.

Notizen: Abstract Cadmium and manganese radionuclide uptake by Zostera marina L. tissues and translocation between rootrhizomes and leaves was examined. Cadmium concentrations in root-rhizomes increased with incubation time but appeared to reach saturation levels at 24 h of exposure. Translocation of cadmium between root-rhizomes and leaves occurred in both directions. A greater flux of cadmium downward suggested that root-rhizomes were a cadmium sink. Cadmium flux in either direction could be enhanced by a salt gradient. Cadmium appears to move through eelgrass by diffusion or mass flow through vascular tissues and apparent free spaces. Manganese is less mobile but is more readily fixed by leaves. Manganese mobility is not enhanced by salt gradients. Incorporation of cadmium and manganese into root-rhizomes from labelled anoxic sediments was several orders of magnitude less than that from labelled anoxic seawater media.

Notizen: Abstract Siliceous nanoplankton in the size range 2.5 to 5.5 μm and of a type hitherto undescribed are reported from Eastern Subarctic water samples. Nine distinct cell types were recognizable, each possessing an unusual tetrahedral symmetry, resulting from the arrangement of 8 siliceous plates. Since the cells were abundant (maximum concentration of about 7×105 cells 1-1) and were distributed over a wide oceanic area (136° to 149°W), they could well play an important role in the food web in Subarctic seas. Similar cells were found simultaneously in Antarctic waters (see following paper: Silver et al., 1980), where they were as abundant and widespread as in the Subarctic. Evidence that the siliceous forms are likely a cyst stage and that they may be part of the life cycle of species of siliceous oceanic choanoflagellates is presented.