ALBERT

Notizen: Summary The apical sensory organ on the antenna ofMetoponorthus was studied by scanning and transmission electron microscopy. It consists of a tuft of very short terminal hairs which prolongs a central body and two long lateral hairs which are articulated on the central body of the sensory organ. Hairs from the terminal tuft are innervated by 4 to 12 bipolar neurons. The dendritic cilia proceed through the axial body and then enter the lumen of hairs without branching. Dendrites in each hair communicate with environment through a rather wide terminal opening. It is suggested that some dendrites are mechanoreceptive. Scale-like cuticular structures protect the terminal part of the hairs, on the inner side that is not exposed to outer stimuli. The two long lateral hairs are innervated by 5 bipolar neurons: 4 dendrites enter the hair lumen while one, mechanoreceptive, terminates in the socket membrane. The fine structure of this apical sensory organ corresponds to that of known contact chemoreceptors in other Arthropods. A comparison is made with known chemo-receptors in marine and terrestrial Crustacea. In terrestrial forms it can be observed that the hairs become shorter. On the other hand the hair surfaces which are not exposed to outer stimuli show a thickened cuticule. In the terrestrial IsopodMetoponorthus (studied in the present work) the very short terminal hairs barely project past the central body. The development of the cuticular structures at the tip of the hairs and the tendancy of the hairs to be integrated into a single organ (central body of the sensory organ) represent so many adaptations for protection and reduction of evaporation.

Notizen: Summary The paired testes of the spider miteTetranychus urticae are divided in a part producing germ cells and a secretory portion with a vast lumen. The secretory part is tubular and is connected to a vesicula seminalis that begins with paired pieces and then becomes unpaired. The penis is composed of two different parts: an evagination of the body wall that is penetrated by the ejaculatory duct and a ventral cuticular invagination the proximal part of which is an insertion for protractor muscles. The ultrastructures of the male genital tract and of the receptaculum seminis of the female are described in detail. The germinal epithelium is built up of a multinuclear somatic cell which envelops the germ cells. The spermiogenesis is characterized by the following features: invagination of the plasma membrane, degeneration of cell organelles, reduction in size and condensation of nucleus and cytoplasm. The germ cells lack flagellum and aerosome. The sperms leave the germ producing part of the testis with roundish shape, the invaginations — now pinched off the cell membrane — are to be seen as peripherally located vesicles. The chromatin is condensed, a nuclear envelope is absent. Mitochondria, a Golgi apparatus and ribosomes are reduced. In the receptaculum seminis the sperms are of irregular shape, they bear finger-shaped processes. Below the cell membrane numerous tubules are to be found.

Notizen: Summary 1. The skeleton of segments VIII, IX and X of the female abdomen is described in 71 species of Adephaga and 13 of Polyphaga. Moreover in nearly 45 of these animals the musculature is studied. 2. In the most primitive case the abdomen of Coleoptera consists of at least 10 segments. 3. With few exceptions segment IX is invaginated into segment VIII in all Coleoptera studied. In almost all cases coxosternum VIII is retracted into the region of sternum VII; tergum VIII is invaginated into the region of tergum VII mostly in part, but sometimes completely or not at all. 4. It is possible to homologisize all elements of the outer female genital organs of the Coleoptera studied with elements of the basic plan of Pterygota. 5. In some Coleoptera the genital appendage of segment VIII is still visible. Within segment IX gonocoxa and stylus (third valvula) are preserved. In many Polyphaga the terminal segment of the stylus is developed in the form of a palpus. In all Adephaga the terminal segment of the stylus is fused with the gonocoxa or reduced. The second gonapophyses do not exist in Coleoptera. The gonangulum is fused with tergum IX. 6. In Adephaga and Polyphaga the gonocoxa is divided into a cranial and a caudal part. Probably the caudal part is homologous to the basic segment of the stylus. 7. The terminal, dorsal plate of the abdomen consists of tergum IX and X in Adephaga and Polyphaga. In most cases tergum IX and X are fused. In the basic plan of Adephaga tergum IX is divided in to two lateral plates, which cover the flanks of segment IX. In some Coleoptera a rest of sternum X is preserved. 8. The gonocoxapophysealmuscle of segment VIII is retained in all Adephaga and some Polyphaga. The two gonocoxotergalmuscles of segment IX exist in all Adephaga and some Polyphaga. 9. In some Adephaga and Polyphaga intertergal- and intersternalmuscles between segment IX and X are present. 10. The construction of the outer genital organs in Rhysodidae seems to be very primitive within the Adephaga. 11. Making use of the synapomorphic characters, which have been found within the terminal abdominal segments, the following phylogenetic conclusions may be drawn: a) The Cicindelidae constitute a monophyletic group. Within the Cicindelidae the Megacephalini represent a paraphyletic group. b) Trachypachini + Metriini + Paussini + Elaphrini + Omophronini + Opisthiini + Nebriini + Notiophilini + Scaritini + Hydradephaga constitute a monophyletic group. c) Carabini + Cychrini + Pamborini + Siagonini constitute a monophyletic group. d) The Harpalinae (sensu Ganglbauer, 1892; Crowson, 1967) represent a monophyletic group. e) Galeritini + Anthiini + Graphopterini + Corsyrini + Mormolycini + Pseudomorphini may be considered as a monophyletic group. Within this group Anthiini + Graphopterini + Corsyrini consist a monophyletic group; the Corsyrini are more closely related to the Graphopterini than to the Anthiini. Next relatives of the Mormolycini are the Pseudomorphini. Anthiini + Graphopterini + Corsyrini represent the sister-group of Mormolycini + Pseudomorphini. The phylogenetic conclusions must not be considered as final, because they are drawn only by means of characters of the terminal segments of the abdomen.

Notizen: Summary The growth of the coronal plates was studied by tetracycline labeling. The compound ambulacral plates (A-plates) of the arbacioid type are secondary triads, developed by the addition of a simple plate (adorad demi-plate) to a diad (primary plate and adapical demi-plate). Adapically the adorad demi-plate is growing independently from the diad. The ambulacra are narrow in the adapical region but orad the ambitus they are widened to phyllodes. The A-plates grow at all sutures, but the ratio of increase is greatest at the adradial suture. — The interambulacral plates (IA-plates) grow mainly in lateral direction. The ratio of interradiad to adradiad increase is 9∶1 (inParacentrotus the ratio is 1 ∶ 1). — InArbacia the peristome is formed by the primordial plates. The unpaired primordial IA-plate (pIA) blocks the interradial growth in the peristome. The primordial IA-plate ofArbacia is homologeous to the “perignathic element” (pG) inCoelopleurus andParacentrotus. Contrary to Lovén (1892) and Gordon (1926) the primordial plates are preserved in many regular sea urchins! — The primordial A-plates (pA) are paired. Each primordial A-plate forms an auricle (Au) and a lateral “ambulacral process” (aF). The ambulacral process is sheathed by the primordial IA-plate. InA. punctulata the primordial IA-plate is partly resorbed and the ambulacral process switches over to the next IA-plate. — In the ambitus the plates are mostly thickened near their adoral suture: Therefore the older (labeled) parts become oblique within their plates. The “ontogenetic variation in c-axis orientation” is a consequence of this.

Notizen: Summary Ephydatia fluviatilis ingests paniculate and dissolved food substances through the incurrent canal system into the “open” mesenchymal space. Particulate food, especially bacteria, is caught by the choanocytes of the flagellated chamber which form a filter-like structure, and phagocytosed by choanocytes and amoebocytes. The capacity of lysosomal digestion in the amoebocytes exceeds that of other phagocytotic cells. Both choanocytes and amoebocytes are able to transfer their phagosomes to other food-searching cells. Excrements released into the mesenchymal space are transported through the endopinacocytes into the excurrent canal system. Dissolved proteins are pinocytosed by the choanocytes at the inner face of the collar base and accumulated in food vacuoles. These are exocytosed at the basal side of the choanocytes and in turn endocytosed and digested by amoebocytes. Residual bodies with contents of lamellate structure are defecated in the same way via the endopinacocytes of the excurrent canals.

Notizen: Summary 1 The egg has about ten micropyles around the forepole. Apart from that the surface is rather smooth, without a pattern, and covered by a wax layer. The chorion is composed of several layers, which are described. It shows adaptations to dry environment. The chorion as a “maternal cuticle” is discussed. 2 A vitelline membrane surrounds the oocyte below the chorion. It consists of three laminae: an electron lucent one between two moderately dense ones. 3 The serosal cells have presumably a dual function. Strongly developed rough ER and pronounced nucleoli point to the manufacture of proteins, probably enzymes which participate in the liquifaction of the yolk.During development the serosa withdraws from the vitelline membrane and secretes a heterogenous product — a proteinaceous (?) fluid, dense granules and lipid droplets — into the peripheral space. Dense granules are derived from the yolk and transported through the cells without morphological alterations, whereas taken up lipids are apparently metabolized. These processes are interpreted as excretory activities, which shall keep the yolk free of waste substances. 4 The same products as in the peripheral space — except for the lipid droplets — are found in the amnion cavity. They are likewise considered as excretory products which are primarily deposited by the germ band cells. The amnion may serve to keep the material in a defined area separate from the nutrition.The appearance of orientated microtubules during katatrepsis may be indicative for an active participation in embryonic movements. 5 Pronounced ultrastructural changes occur during transition from ectoderm to epidermis. Ectodermal tissue is characterized by the presence of electron lucent vesicles and free ribosomes. It also secretes the “first embryonic cuticle” (“Cut. I”), a trilaminar membrane which probably represents a cuticulin layer. Besides ectoderm and several ectodermal organ anlagen also the amnion forms this membrane. (Endocrine glands are not yet active.) In this context some aspects of differentiation and determination are discussed. The embryonic epidermis contains no electron lucent vesicles, but many pigment granules. It secrets two more “embryonic cuticles” (“Cut. II and III”) which have the structure of a typical larval one prior to ecdysis (endocuticle=procuticle). A wax layer, however, is already present. “Cut. III” represents the first larval cuticle.

Notizen: Summary 1) The present article deals with the morphology of the olfactory organ ofLampris guttatus (Brünnich) and its functional correlation with the neighbouring lacrymal bone and the jaw apparatus in respiration. 2) The nasal cavity consists of a rather tube-like atrium, a flat ethmoidal nasal groove and a somewhat spherical nasal pouch. 3) The olfactory tissue only covers a small area and forms a semicircle of rounded laminae lying in the atrium beneath the paired and minute nostrils. 4) The dermal bridge separating the nostrils has no vertical sail. The water current inside the nasal cavity therefore is exclusively effected by a specific irrigation mechanism. 5) The lacrymal bone is rather moveably suspended from the neurocranium and shows functional connection with the jaw apparatus. Whenever the jaws are protruded or retracted the lacrymal bone is slightly rotated downwards resp. upwards. 6) By this slight rotation around its articulation with the lateroethmoid the lacrymal bone alternately indents and tightens the membraneous roof of the ethmoidal nasal groove in order to ventilate its cavity. 7) The lacrymal nasal pouch is ventilated by a joint facet formed of both mandibula and maxilla and by the lacrymal bone. 8) Experimental verification of the described ventilation mechanism by imitation of the supposed natural movement pattern showed that in adult specimens at least one tenth of the total volume of the nasal cavity is exchanged in the course of each respiration resp. irrigation cycle. 9) The olfactory organ ofLampris guttatus functionally is monotrematic; the water current flows inward through both nostrils simultaneously (aspiration) and flows out in the same manner (expiration). 10) The ventilation of the nasal cavity is comparable to the function of a pipette. Due to the rhythmic deformation of the ethmoidal nasal groove and the lacrymal nasal pouch only the rostral part of the atrium with the olfactory tissue is permanently irrigated by fresh water. Thus even slight movements of the jaw apparatus seem to be sufficient for an extensive olfactory control of the environment. 11) Comparison of the retina and olfactory tissue areas seemingly provesLampris guttatus to be a marked ‘ophthalmic’ fish. The presence of such an effective irrigation mechanism, however, may well indicate a considerable biological significance of its olfactory organ.

Notizen: Summary The growth of the skeleton of the lantern of Aristotle is studied by tetracycline labeling in the stirodontArbacia lixula and in the camarodontParacentrotus lividus. The pyramids support and guide the teeth. They are built up by two demipyramids (Ki) which are heightened intensively especially apicad. The ratio of apicad/orad increase varies between 1,3 ∶ 1 and 4,3 ∶ 1. In the lateral direction the demipyramid grows mainly at the symphysis of the pyramid; in the radial direction it grows at its abaxial surface. The “growing center” of the demipyramid is eccentric. The orad top of the pyramid is exposed to a fixed end moment when the tooth scrapes. The growth of the lantern is accompanied by an increase in moment, and in proportion to this increasing stress the top of the pyramid is thickened at all its surfaces. The joints of the lantern are formed between epiphyses and rotulae. The articular surfaces are covered by polycristalline calcite. During growth the articular surfaces move apart. Polycristalline calcite can not to be transformed into monocristalline calcite, therefore the polycristalline cover of the articular surface is to be renewed and resorbed continually. The epiphysis has three eminences (Ci–C3) and a glenoid groove (Gl) at its perradial surface. During growth the epiphysis is thickened on its opposite surface. The large condylus C1 growth in the abaxial direction and its polycristalline cover is thickened. C2 and C3 are shifted adaxiad. Their delicate polycristalline covers are continually built up adaxiad and the old parts become resorbed. The rotulae have condyli (cond) and grooves (A1–A3) onboth sides. The rotula growths proportionally in laterad and in radiad directions, but in height the growth is only apicad. During growth the joints move apart in all directions, and their polycristalline cover is renewed continually. From the orad surface the oldest parts of the rotula are resorbed, including the polycristalline cover of the joints, which have become too small. By means of this unusual mode of growth the rotula and its articular surfaces are enlarged in correspondence to the growth of the epiphysis and its articular surfaces! In both species examined there are great differences in coronal growth, but their lanterns work and grow in a very similiar manner.

Notizen: Summary Phase-contrast and electron microscopical investigations of the pancreatic appendages of the Ductus hepatopancreas in Sepioidea (Sepia officinalis L., Sepia elegans d'Orb.,Sepietta obscura Naef,Sepiola robusta Naef) of different age groups (newly hatched, juvenile and adult animals) show a basic conformity in the arrangement and ultrastructure of the organs in the species studied. The appendages are composed of two epithelia, which are separated by a blood sinus. They have a congruous polar structure marked by: a brush border, a basal folded labyrinth, a high content in mitochondria and dense bodies. The differences in the structure of both cellular layers and their morphological changes, which are related to age and nourishment, suggest that the inner epithelium lining the duct has a dual function, serving excretion and nutrient absorption. The rather flat outer epithelium, which faces the renal cavity, can be associated mainly with processes of osmoregulation and urine formation.

Notizen: Summary The coronar growth of a cidaroid and an aulodont echinoid are investigated by means of tetracycline labelling. The results are compared with earlier investigations on a stirodont and on a camarodont echinoid in order to evaluate the general features of coronar growth. In all echinoids new coronar plates are added at the apical end of the corona throughout the life cycle. The plates are shifted towards the peristome and they grow peripherically. In cidaroids ambulacral (A-) plates are detached from the firm corona. They are transformed into scales covering the peristomial field. The interambulacral (IA-) plates, however, are partially reabsorbed at the peristomial margin. In this manner the oldest solitary interambulacral plates are lost. The subsequent plates are arranged in pairs. The cidaroids thus show interradial growth even at their peristomial margin. This is unique to echinoids. In non-cidaroids there is a perignathic girdle made up of paired ambulacral auricles with interambulacral ridges in between. In some species the ridge is a solitary element. Therefore interradial growth cannot occur in the peristomial margin. In other species the ridge consists of several elements, but it also grows as a whole. Slight resorption of calcite occurs in places at the peristomial margin. In other places, however, calcite is added onto the peristomial edge. In non-cidaroids, therefore, the widening of the peristome is achieved solely by means of lateral growth in the plates bordering the peristome. The shift of the coronar plates from apicad to orad in noncidaroids is a relative shift only. In all echinoids the coronar plates are arranged in meridional columns. All plates grow up to the peristome. Their growth rates are relatively uniform towards the adambulacral sutures (which run between A- and IA-columns). Their growth rates towards the perradius and the interradius respectively are high in younger plates which are positioned above the ambitus, and decrease rapidly in plates located below the ambitus. Near the peristome the interradiad and perradiad growth rates are always considerably lower than adradiad growth rates. Perradial and interradial growth serve to adjust the plates in size and shape to their respective position in the corona.

Notizen: Summary The ultrastructure of the shell gland of Microdalyellia fairchildi (Graff) is described. The gland is composed of two types of secretion cells termed gland cell I and II. The first type consists of two bundles of large flasklike cells placed in opposite positions at the proximal ovovitelloduct. Distinguishing features of these cells are the amply developed rough E.R. with distended cisternae, forming several circular or elongate vesicles, which contain a granular substance, the long cell process with densely packed secretion vacuoles constituting a honeycomblike structure, and autolysosomes. No condensed material is seen in the vacuoles. The process terminates with a narrow channellike part lined by peripheral microtubules and forming septate desmosomal junctions with the epithelial cells of the ovovitelloduct, into which the cells open ventrolaterally. The second cell type is likewise arranged in two lateral clusters at a more distal part of the genital duct. The cells are essentially smaller and the rough E.R. has the usual appearance with flattened cisternae. The secretion bodies are surrounded by a membrane and contain a central core of dense granular material. Some autolysosomes are also present. The fine structure of the endpiece of the process passing through the ventrolateral epithelium of the ovovitelloduct is similar to that of the gland cell I. There are special similarities between the first cell type of Microdalyellia and certain Mehlis gland cells of parasitic flatworms termed S2 cells in Trematoda, indicating that these are homologous. On the other hand there are no such hints concerning the gland cell II and another cell type of the Mehlis gland called the S1 cell.

Notizen: Summary The development of abdominal segments in Spirorbis moerchi (Polychaeta: Annelida) was studied by light and electron microscopy. Abdominal segments develop in strict succession from anterior to posterior. Segmentation is initiated in the mesoderm and is followed by segmentation of the ectoderm. The mesoderm of the abdominal segments arises entirely from pygidial residual mesoderm; inward migration of cells from the pygidial ectoderm to give rise to mesoderm does not occur. The primordial germ cells remain distinct from the residual mesoderm of the pygidial growth region. After several abdominal segments have developed, the primordial germ cells “migrate” posteriorly from the achaetous region, invade the abdominal segments, and give rise to the retroperitoneal gonads. Abdominal segment formation is discussed in terms of heteronomy, primordial germ cell origin, gonad formation, and development of the circulatory system.

Notizen: Summary The cerebral and epidermal ocelli of the Müller's larva and the cerebral and tentacular eyes of the adult turbellarian Pseudoceros canadensis were studied by electron microscopy. The right cerebral ocellus of the larva consists of one cup-shaped pigmented cell and three sensory cells that bear microvilli. The left cerebral eye of the larva has the above named cells plus a sensory cell with many cilia. Evolutionary significance is attributed to the presence of both ciliary and microvillar photoreceptors in an eye of a flatworm. The one epidermal ocellus of the larva is composed of two cells: a cup-shaped pigmented one bearing flattened cilia, the presumed photoreceptors, and a cell above the cup that adds a few nonciliary lamellae to the stack of ciliary ones from the pigmented cell. The adult eyes contain only microvillar receptors; cilia were not observed.

Notizen: Summary 1. The cells of the ventral epithelium form no microvilli but a spongy meshwork of fenestrated ledges and folds which may play a rôle in the adhesion of the animal to the substratum and/or in the extrasomatic predigestion of the food. 2. During cell division typical centrioles occur at the spindle poles. 3. The growing egg cells phagocytize projections of the fiber cells which function as trophocytes. 4. Under the same conditions leading to egg formation so-called S-cells may occur. Some ultrastructural data suggest that they are sperm cells.

Notizen: Summary The mesogastropod Pyrazus ebeninus, produces true spermatozoa (here termed euspermatozoa) and multi-flagellate, mobile cells (here termed paraspermatozoa). The mature paraspermatozoon consists of an elongateconical ‘head’ (6.5–8.5 μm in length), constructed of an electron-dense mosaic sheath surrounding a similarly dense, rod-shaped nuclear core (which runs almost the full length of the head). An acrosome-like structure forms the apex of the head. Five to eight axonemes are fixed to the posterior extremity of the nuclear core, each by means of an attachment complex (dense attachment rod, centriolar cap and centriole). A short (3–4 μm) ‘midpiece’ zone follows the head and consists of the multiple axonemes interspersed with very elongate mitochondria. A tuft of short (20 μm) tails (termed minor tails) emerges from the midpiece in addition to one very long tail (termed the major tail) ensheathed in dense granules which resemble glycogen granules. A single membrane surrounds head, midpiece and tails whilst the nuclear core retains the original double nuclear membrane. Developmentally, the multiple axonemes arise from one of a pair of wheel-shaped arrangements of centrioles and attach to posterior indentations in the nucleus prior to its transformation into the nuclear core. Dense vesicles, derived apparently from the endoplasmic reticulum, accumulate along and around the developing nuclear core and (in the presence of microtubules) condense into the mosaic head sheath. Cytoplasmic mitochondria elongate and collect at the posterior axis of the cell, where, together with the axonemes, they form the midpiece. Features not previously reported in other ultrastructural studies of paraspermatozoa include the acrosome-like structure of the head, the structure of the midpiece zone, the glycogen sheath of the major tail, the dense annular structure at the junction of the midpiece and major tail and the presence of microtubules in the final phase of head and midpiece maturation. Some features of the euspermatozoon are also described and the comparative ultrastructure of mature and developing paraspermatozoa and their possible functions in the Gastropoda, are reviewed.

Notizen: Summary A previously undescribed receptor in the coxo-trochantinal region of the metathoracic leg of the cockroach Periplaneta americana was found to have central cell bodies. This cockroach stretch receptor is the second sensory receptor in insects reported to possess somata in the CNS and its remarkable similarity to a locust proprioceptor suggests it to be homologous.

Notizen: Summary The structural organization of the ocelli of several diplopod species has been studied by means of electron microscopy. The results provide evidence that diplopodan ocelli are derived from typical mandibulate ommatidia, which consequently had been present in diplopod ancestors. The recent representatives of the two sister groups, Pselaphognatha and Chilognatha are characterized by two essentially different types of eye morphology: The eyes of the Pselaphognatha comprise a bilayered rhabdom (built up by 3+4 retinular cells), a few corneagenous cells, a corneal lens, and two vitreous bodies. The latter probably represent relics of a former crystalline cone. On the contrary, the ocelli of the Chilognatha consist of a multilayered rhabdom (built up by a large number of retinular cells), numerous corneagenous cells, and a corneal lens. The dioptric apparatus lacks a crystalline cone. Further structural elements, the distribution of which varies, are the covering cells and processes of hypodermal cells which contain screening pigments. Whereas the eye of the Pselaphognatha can be traced back to a single ommatidium, the ocellus of the Chilognatha can only be interpreted as a merging product of several associated ommatidia or as the result of multiplication and rearrangement of former ommatidial elements. This concept is substantiated by analogous phenomena which occur within other arthropod groups and thus serve as models for the phylogeny of the diplopodan eyes. The comparison of the morphology and the ecology of palaeozoic and recent diplopods demonstrates that the disintegration of former facetted eyes and the modification of ommatidia were induced by the adaptation to cryptic modes of life.

Notizen: Summary Some of the changes which occur in wood during the transition from sapwood to heartwood have been reviewed. The nature of these changes suggest that heartwood formation is a regulatory process serving to keep the amount of sapwood at an optimum level. The pattern formed by the transition of cells from sapwood to heartwood suggests that heartwood development is controlled by a centripetally-translocated growth-active substance. The nature of the heartwood transformation is indicative of a developmental process rather than a deterioration of cell function with age so that death of the parenchyma cells is the result and not the cause of heartwood formation.

Notizen: Abstract The Young's and shear moduli of two lignins have been measured at several moisture contents. Cylindrical test specimens moulded from periodate and Klason lignin powders were conditioned to the required moisture contents and tested in tension and torsion. The Young's modulus of periodate lignin increased linearly from 3.1x109 to 6.7x109 Pa, and the shear modulus from 1.2x109 to 2.1x109 Pa as the moisture content of the lignin decreased from 12 to 3.6%. Klason lignin showed similar behaviour but its moduli were always much lower. This was probably a consequence of the more drastic alteration undergone by the Klason lignin during its isolation from the wood cell wall.

Notizen: Abstract A means to quantitatively construct two layer models of the wood cell-wall utilising basic density and mean microfibril angle data is discussed. It is assumed that the lignin distribution is uniform in the secondary wall layers, that there is a fixed polysaccharide ratio throughout the wall and that variation in wall thickness arises only from variation in S2 layer thickness. It is shown that the relative thickness of those cell wall layers in which the cellulose is transversely oriented (M+P, S1 and S3) have a significant effect on longitudinal shrinkage and that variance between computed and measured shrinkage values is reduced when compared with earlier models if both basic density and mean microfibril angle are taken into account.

Notizen: Summary Fines removed from the surfaces of Pinus radiata fibres by beating were identified and characterised in terms of microfibril orientations in the surfaces of beaten fibres. Fines fractions subjected to chemical analyses were selected so that chemical component data could be related to specific layers or lamellae in fibre walls. Carbohydrate distributions within the walls of kraft fibres differed from those in bisulphite fibres. In the kraft fibres, glucomannan increased and other hemicelluloses decreased from the primary wall to the outer lamellae of the S2 layer of the secondary wall. In the bisulphite fibres, hemicelluloses were uniformly distributed throughout the outer wall layers, i. e., the primary wall and the S1 and outer lamellae of the S2 layers of the secondary wall. More galactan but less arabinan, xylan, and glucomannan were found in the outer layers than in the inner layers of the bisulphite fibres. Carbohydrate distributions were determined for a range of bisulphite pulp yields (53 to 80 percent). The outer layers of the bisulphite fibres contained more Klason lignin than the inner layers. Acid-soluble lignin contents were similar in the inner and outer layers.

Notizen: Summary The effect of the number and the location of glue lines in the cross section on the bending properties has been studied on plywood bonded with tannin-formaldehyde adhesive. The thickness of glue line has also been investigated. By comparing the theoretical equations with the empirical ones, we can get the thickness of the glue line of wattle tannin adhesive plywood to be 0.15 mm. As for Young's modulus in bending of the glue line in the plywood, it is calculated to be 219 800 kg/cm2 and is larger than that of the glue line of phenolic resin bonded plywood. In relation to the veneer, Young's modulus of the veneer under the condition of plywood assembly seems to be slightly larger than that of the veneer under the free condition.

Notizen: Summary As the world's supply of non-renewable resources becomes increasingly critical, wood with its many attributes, but also with some inherent problems, has the opportunity of playing a more and more important role in meeting a wide variety of man's needs. Research and the development and utilization of research findings will be most important in determining how well wood fares in the years ahead. Those involved in the research effort must be aware of the need to select problems which if successful solutions are found can aid wood in better meeting man's needs. Also, there need be the recognition that the solution will only find use, if in addition to the problem being deemed of importance, both technical and economic feasibility to a significant degree can be demonstrated. The industrial rather than the scientific community is the final judge.

Notizen: Summary Morphological and chemical examinations of the extractives of the tissues and shake contents of eight Dacrydium and one Podocarpus species have been made. The whitish deposits in heart-shakes are without exception mainly podocarpic acid (PCA). This compound occurs also in the tissue of samples but only when shakes are found nearby. Accordingly PCA is regarded as an anomalous extractive, synthesized in response to those conditions resulting in shake formation. In samples with shakes PCA is present in very small amounts at the sapwood-heartwood boundary and in one sample there were traces even in the innermost sapwood. It was notable that shakes containing deposits can arise in those Dacrydium species with coloured heartwood and with a known tendency for wetwood formation. On the other hand Dacrydium franklinii does not develop coloured heartwood or wetwood or shakes, and the lack of these features may have taxonomic significance.

Notizen: Summary The mixture of monomeric phenols obtained by hydrogenation of wood from Eucalyptus diversicolor was analysed by GLC and tested for lipid antioxidant activity, which was found to be 75% of that of 2-t-butyl-4-methoxyphenol (BHA). Butylation decreased antioxidant efficiency. Increased demethylation was observed at higher hydrogenation temperatures.

Notizen: Summary A differential and an integral method of kinetic analysis of the data from isothermal pyrolysis of two pulps have shown that a cotton linters pulp has a lower activation energy throughout the entire reaction than has a bleached pine kraft pulp. In all cases, the activation energy decreases with increasing conversion. The mean values obtained were 30 and 36 kcal/mole by the differential and integral methods, respectively, for pyrolysis of the cotton linters pulp and 42 and 45 kcal/mole, respectively, for pyrolysis of the bleached pine kraft pulp. Neither method of analysis used in this work requires prior determination or empirical statement of the reaction order n. This is essential to a proper analysis since it has been shown that the reaction order cannot be regarded as a constant if the complete pyrolysis reaction is studied.

Notizen: Summary This paper surveys the different kinetic schemes that have been employed with dynamic thermogravimetric analysis and discusses their advantages and shortcomings with particular reference to cellulose. It is concluded that the differential method of Friedman [1965] and the integral method of Flynn and Wall [1966] are the best approaches for kinetic analysis in each category. Both these methods are consistent with and analogous to the isothermal kinetic methods previously given by Cardwell and Luner [1975].

Notizen: Summary Characteristic features of wood deformation under loading at changing moisture contents (temperature) are discussed on the basis of results from rheological tests with hardwood. General laws of deformation in wood as a result of various cyclic effects of loading as well as of temperature and moisture content have been established. These laws have been used to solve the problem of the plane stress state in lumber when dried by using the “method of finite elements”. To control internal stresses and for an effective drying process, it is suggested that differential shrinkage should be measured, i.e. the difference between the displacements of points on Both verges of the board's edge and in the centre of the edge.

Notizen: Abstract The variation of the coefficient of friction with normal load and tool surface finish in slow speed orthogonal cutting of white fir was investigated to determine the relative importance of different sources of friction. Cutting forces were measured as a function of tool-chip contact length and tool surface roughness. The coefficient of friction was independent of tool roughness for roughness in the range of typically well-finished cutting tools but did become a factor for large values of tool surface roughness. The data indicate that for well-finished cutting tools the primary friction mechanism is adhesion between the tool and work and that for rough tool surfaces the effect of tool surface asperities (unevennesses) as they advance through the chip becomes an important source of friction.

Notizen: Summary The thick-walled bamboo fibres exhibit a polylamellate structure with alternating broad and narrow lamellae. Characteristically the cellulose fibrils in the broad lamellae are oriented almost parallel to the longitudinal axis of the fibre (2–20°), whereby there is a gradual but only slight increase in the angle from middle lamella to lumen. The narrow lamellae consist of fibrils oriented almost perpendicular to the cell axis (85–90°); this angle remains constant in all the successive narrow lamellae. The concentration of lignin is higher in the narrow lamellae than in the broad ones. Xylan seems to occur in a higher concentration in the narrow lamellae. The pits between the fibres are bordered. The results are discussed in relation to earlier data on wall structure and development. A model for the thick-walled bamboo fibre is presented with a new terminology for the various lamellae.

Notizen: Abstract The percent explained variation (r2) of tensile strength (T) of dimension lumber can be accounted for primarily by apparent modulus of elasticity (Ea). Tensile strength ratio, a good index of T of structural lumber, and Ea are both dependent on relative knot size, making T a function of Ea. This theoretical relationship helps to increase r2 when T is regressed on Ea and gives the “cause and effect” for some multiple regression analyses. An independent variable was identified on the basis of this theory. Shortening the gage length enhances ability to predict T when flatwise bending Ea or tension Ea is used as an independent variable, but not when edgewise bending Ea is used. Two single variables not previously reported, Ea measured in flatwise bending on 16-inch gage length (EF 16) and Ea measured in tension on 6-inch gage length (ET 6) (based solely on deformation measurements), are individually able to explain approximately as much variation of T (r2=0.75) as the combination of Ea measured flatwise on 48-inch gage length (span length for the existing American grading machines), and ASTM bending strength ratio. The combination of EF 16 and ET6 can explain 85% of the variation of T. The highest r2 (0.87) was obtained when a modified bending strength ratio was added to these new variables.

Notizen: Summary The alkali extract (5% KOH) from beech holocellulose was fractionated by ion exchange chromatography, resulting in several fractions containing different amounts of polyoses and lignin. The separated polyoses varied to some extent in the ratios of their sugar components. Three different 4-0-methylglucurono-xylans and three arabinogalactans were isolated. There was a direct relationship between the chemical composition and the ultrastructure of the fractions. Those containing a pure 4-0-methylglucurono-xylan showed bundles of thin and stiff fibrils while in fractions with a high percentage of lignin coiled fibrils and globular particles could be observed in the electron microscope.

Notizen: Summary That the behavior of wood in service results from its “structure” is generally accepted by wood scientists. No doubt this acceptance is due to the broad interpretation of such a term. Structure can refer to the organization of elements on a macro scale, such as in a laminated beam, as well as to the arrangement of cellulose molecules in the crystalline region of an elementary fibril. This presentation focuses on a structural domain that appears increasingly to be a critical one in wood behavior-ultrastructure. The spectrum of terminology that has been used in profusion during the “electron microscopic era” must first be defined so that confusion is minimized. Then a historical evolution of the field of wood ultrastructure can be presented to provide perspective. Structures that have been shown to affect or indeed to control certain processes can be identified. The role of a “non-structure”, the elusive transient capillary, can be illustrated. Microfibrillar organization and cell wall archictecture fall into the realm of ultrastructure as well. The past decade of research in wood science has been productive to a significant extent because of scanning electron microscopy and its accessory tools and techniques. The exploration of wood penetration by wood preservatives, pulping liquors and coatings using this approach has yielded much new evidence. One can speculate about the anticipated contributions of computer-driven SEM, stereology, STEM, and even higher resolution microscopy in the near future.

Notizen: Summary Problems associated with handling non-steady liquid flow data are discussed. It is shown that the Darcian flow model is fundamentally imprecise when applied to non-steady state flow in wood due to: 1) the observed decrease in permeability with increased specimen length 2) the wide range of diameters encountered in wood pores. Because of this wide range of pore sizes, liquid penetrates some flow paths more rapidly than others. This may give rise to the occurrence of surface forces resisting penetration, with both “wetting” and “non-wetting” liquids. It seems unlikely that these various factors can be accurately quantified. Hence the precise prediction of liquid penetration rate from steady state permeability data may be illusory.

Notizen: Summary To predict the capillary transport of free liquid during the drying of softwood, it is essential to have knowledge of capillary pressure as a function of moisture content. The dependence of the capillary pressure on the wood's moisture content is predicted with a mechanistic model and measured for isothermal moisture movement in the tangetial direction. The experimental measurements confirm the model which is formulated on the postulate that the menisci that form between the liquid and gas in the tracheid lumens control the magnitude of the capillary pressure. Lumen size variation within an annual growh ring was found to significantly affect the local capillary pressure and indicated that separate flow paths are likely to exist in earlywood and latewood.

Notizen: Summary A model for the build up of residual growth stresses in cylindrical tree stems is presented. By using Bessel functions the general equations can be solved to allow for surface strain distributions that vary both in the circumferential as well as longitudinal directions. An arbitrary surface strain distribution can be decomposed into Fourier components and the residual internal stresses can be found by superimposing the component solutions due to each new increment of growth. A numerical simulation leading to the residual stress distribution for a typical hardwood is presented.

Notizen: Summary Information is presented on the magnitude of errors associated with various sampling simulation schemes of the distribution of three different populations, representing actual bending strength of dimension lumber. Errors were determined between the simulated and actual distributions. Graphical evaluations indicated good fits with the three-parameter form of the weibull distribution for both original and simulated bending strength data, as well as with the resulting error terms. Error terms, based on the simulated versus actual distributions, were generated for the lower 5% exclusion limit, for the 50% exclusion limit and for the entire distribution curve. Simulations were carried out with the aid of Monte Carlo techniques using distribution functions fitted to actual test data for dimension lumber. The errors are expressed as functions of confidence levels. The comparison of the erro obtained through the various sampling schemes could provide some initial directions to choose an economical sampling plan for the presently ongoing in-grade lumber testing program.

Notizen: Summary Paintings on 150 wooden panels accepted and not accepted as authentic Rembrandts were investigated using wood-anatomical and dendrochronological techniques. Paintings on 131 panels came from oaks in the coastal area of the Netherlands and 1 panel came from an oak in the interior. The wood of the remaining 18 panels was from beech, poplar and walnut, presumably from the Netherlands, and from cedrela, mahogany and jequitiba imported from Central and South America. In several cases wood of different panels was from the same trunk. By determining the felling date of a tree, a “terminus post quem” could be set for the production of the panel and the completion of the painting, respectively. The art-historical dating of most paintings could be dendrochronologically confirmed. In some cases the attribution was corrected by a few years. In one case an older panel was re-used.

Notizen: Summary Structural factors in a Pinus densiflora tree grown under the influence of strong wind were measured. No $$\overline {DP} $$ difference for cellulose molecules was noticed between compression and opposite wood, but the $$\overline {DP} $$ was somewhat lower in the region where the compression wood was concentrated. The degree of crystallinity of cellulose was 45–50% in compression wood, about 50% in normal wood, and 50–60% in opposite wood. The crystallinity decreased with increasing height above the ground. The maximum point of crystallographic b-axis (fiber axis) orientation distribution for cellulose crystallites in compression wood was located at ϕ≅30°, in normal wood at ϕ≅25° and in opposite wood at ϕ≅0°. The cellulose crystallite dimension in the transverse direction was 3.2 nm, corresponding to four cellulose unit cells, a value that was almost constant throughout the wood. In the longitudinal direction, there were large differences in cellulose crystallite dimensions between compression and opposite woods. In compression wood the cellulose crystallite dimensions was 12 nm corresponding to 11–12 cellulose unit cells. In opposite wood it was 17–32.5 nm corresponding to 17–32 cellulose unit cells. These structural factors were apparently affected by the environmental conditions, and the mechanical properties of the wood were influenced by these factors. Opposite wood had longer crystallites, a higher degree of crystallinity and a better orientation distribution of cellulose crystallites in the longitudinal direction. Compression wood, on the other hand, had shorter crystallites, a lower degree of crystallinity and a large angle between the stem and the direction of the crystallites.

Notizen: Summary Wood poles have been traditionally tested by “sounding” — striking with a hammer and making a subjective assessment on the basis of the sound emitted. Various other acoustic methods have been developed and employed for this function but none has been accepted on any regular basis as being successful. The propagation of acoustic waves in poles is examined here, and measurements are made using a pulse echo technique of the two acoustic parameters, velocity and damping, on a selection of poles some of which contain decay and rot. The results suggest that measurement of the acoustic damping of longitudinal compression waves may be useful in detecting the presence of decay and rot within a pole.

Notizen: Summary The ophiocephalous pedicellariae of three adratic species of sea urchins have been investigated by the aid of scanning electron microscope regarding the structure of the skeletal ossicles and by the aid of light microscope to elucidate the function of muscles und connective tissue structures. Each valve bears a double central and 2 simple peripheric articulations. Their interactions cause synchronous movements of the 3 valves as well as they enable the peripheral gripping teeth to meet exactly whilst the jaws are closing. Beside the basic handles, which pass over each other when the valves are moving, so-called Innenbügel are arranged at the base of the central articulation of 2 valves. They bear the insertions of the 2 collagen ligaments, which connect the neck with the head of the pedicellariae, without hampering movements of jaws. In the region of the handles, the connective tissue consists of 2 collagen ligaments, which run loop-like over the edges of the handles. Position and structure allow them to increase the gripping power and to lock the articulations for a longer period without the aid of the muscles. The movements of the flexible neck, necessary for the function of the whole pedicellariae are produced by interplaying of the Mm. flexores and the connective tissue stem, which is acting like a hydroskeleton.

Notizen: Summary This investigation of the female genital organs of members of the Gyrinidae, Haliplidae, Noteridae, Dytiscidae and Hygrobiidae serves as a contribution towards the knowledge of the phylogenetics of the Hydradephaga. A comparison is presented of the skeleton, the musculature of the genital segments VIII and IX as well as of the arrangement of the inner genital organs. 1. The female abdomen is bordered distally by the tergite VIII and the sternite VII. Ventral parts of the VIIIth segment (gonocoxosternites, genital appendages VIII) and the IXth segment are invaginated. Sclerotized relics of the postgenital segments are missing. These segments have probably been incorporated in the anal cone. 2. The Hygrobiidae and the Dytiscidae (Amphizoidae ?) possess a double genital opening, the bursa copulatrix and the vagina are separated. In the other Hydradephaga as in the Carabidae there exists a bag-like vagina with a cranial bursa. 3. The dorsally separated bursa copulatrix is missing, considering the Dytiscidae, in the Dytiscinae. The ductus receptaculi and the ductus seminalis have their orifices in the vagina. 4. The protractor of the tergal half of segment IX (M 15) connects this with the gonocoxosternite and serves to move the ovipositor outward. The retractor function is performed by a part of the dorsal longitudinal musculature of the VIIIth segment (M 18) and by a muscle originating cranially at the gonocoxosternite (M 13). 5. The tergogonocoxal muscles (M 32, M 33) originate dorsocranially at the inner surface of the tergal half of segment IX and insert cranially viz. caudally of the tergogonocoxal articulation at the gonocoxa. 6. Numerous muscles originate at the inner surface of the gonocoxa which is distally shaped like a hollow cone. These muscles insert cranially or medially at the bursa copulatrix respectively the vagina. In all Hydradephaga one muscle originates at the genital appendages VIII and inserts at the vagina (M 37). 7. In the copulation the penis is introduced into the bursa (Hygrobiidae, Dytiscidae excluding Dytiscinae) where the spermatophore is placed (in the Dytiscinae it is placed into the spermatophore-pouch in front of the genital opening). In the other Hydradephaga (Gyrinidae, Haliplidae andNoterus) the penis is introduced into the bag-like vagina, where the spermatophore is placed. 8. Hygrobia and the Dytiscidae possess a muscle which connects the gonocoxa with the sklerotized parts of the genital appendages VIII (vulval sclerites) (M 36). 9. The Gyrinidae, Haliplidae and Noteridae (withoutNotomicrus) are characterized by a cranially directed tergal half IX. At the frontal end of this claps both tergogonocoxal muscles originate. 10. The Haliplidae andNoterus have the divided protractor of the gonocoxosternite (M 6) in common. The two muscles function as antagonists (synapomorphic character). 11. In the Gyrinidae the gonocoxal sternites are fused ventromedially, the gonocoxae and the tergal halves IX are placed horizontally. 12. Within the GyrinidaeDineutes andMacrogyrus are more closely related. 13. The systematic position of the genusNotomicrus, which surely does not belong to the Noteridae, could not be settled. 14. Within the Dytiscidae the Dytiscinae form a monophyletic group. The gonocoxa are fused together. A dilatator of the genital appendages VIII and a levator of the membrane above the gonocoxae (levator of the spermatophore-pouch) are present only in this group. 15. The monophyletic character of the Hydroporinae is proved by a muscle between tergite VIII and the free-laying gonocoxa as well as by a retractor of the gonocoxa, which originates cranially at the gonocoxal sternite. 16. The tergite IX is reduced in all Hydroporinae, the cranial process of the gonocoxa replaced functionally a cranially directed clasp-shaped tergite (Gyrinidae, Haliplidae,Noterus). 17. The subfamily Colymbetinae (Dytiscidae) is a “stage group” and not a monophyletic unit. 18. Agabetes (up to now Agabetini resp. Copelatini within the Colymbetinae) andLaccophilus (Laccophilinae) form together a monophyletic group. Both genera possess a saw-shaped ovipositor, which is formed by the genital appendages VIII. 19. Agabini and Colymbetini are “sister-groups”. The genusCopelatus shows affinities with each of the other Dytiscidae-groups. The characters of the ovipositor did not allow a clarification of its systematic position. 20. Knife-like ovipositors for cutting plant tissue are present inDytiscus andCybister. Ilybius andHydrovatus possess saw-shaped gonocoxae, whereas inLaccophilus andAgabetes the genital appendages VIII are saw-shaped.

Notizen: Summary Spermiogenesis and structure of the double sperm have been investigated inAcilius sulcatus andDytiscus marginalis whereas only mature double sperm have been studied inHydaticus transversalis. The conjugation of the sperm in these species is accomplished as a last step in the distal part of the vas deferens. Preconditions for the pairing are local differentiations of the sperm membrane in combination with specific layers of polysaccharids. According to their aspect as well as the chronological order and place of their appearance four such layers can be discerned. These are formed in part still in the lumen of the cyst, in part not earlier than after the anterior ends of the sperm have deeply entered into recesses of the surrounding cyst wall cells. Single sperm supplied with all layers and cytoplasmic remnants pinched off from the cyst wall cells enter the vas deferens where the cytoplasmic remainders are phagocytised by its epithelial cells. The layers of the sperm are transformed after conjugation. Thus as a last precondition for the occurrance of pairing a reaction in the vas deferens must take place. Furthermore, the development of the structural element of the tail described as “microtubular border” has been traced and identified as a “centriole adjunct” derived from nuclear material and modified to a body accompanying the flagellum. Finally, it is pointed out that apparently regular relationships in temporally correlated sequence exist between the endomembranous system and differentiating structures of the spermatid.

Notizen: Summary At the head ofTurbanella cornuta (Gastrotricha) three types of sensory devices are recognized. Thesensory hairs are primary and bipolar cells with an apical cilium that is surrounded by sterocilia. Theposterior sense organ of the head contains 12–14 primary and bipolar sensory cells. These cells and some secretory cells form an extracellular lumen, where the dendrits of sensory cells penetrate with several swallen terminals. Concerning theanterior sense organ of the head two dendrits penetrate into a common lumen and branch out into a lot of regular microvilli, each of which contains one single microtubule. The dendrits of the anterior and posterior sense organs are separated into an inner and an outer segment by a ciliar region. Probably the described sensory devices are coordinated to different functions. It is discussed wheather the sensory hairs have a mechanical function, the posterior sense organs of the head have a chemical function and the anterior sense organs of the head are sensitive to light.

Notizen: Summary Number and distribution of sensilla and setae on the antennal flagellum of the honeybeeApis mellifera carnica were determined on whole antennal preparations. The following types of sensilla were distinguished according to their cuticular structure: Sensillum placodeum, S. ampullaceum, S. coeloconicum, S. basiconicum, S. campaniforme and 5 hair sensilla S.trichodeum A, B1, B2, C, D, as well as 4 types of probably non-innervated setae (A1–3, B). The names used here for the different types were compared with the previously used terms. Number and distribution of sensilla, the number of sensory cells and the function of the sensilla were discussed with respect to the data available from the literature. There is a notable dimorphism between the worker and drone with respect to the relative number of sensilla of each type and to the total number of sensory cells. The worker has far more of the presumably olfactory S. trichodea A and of the mechanoreceptive S. trichodea B1. The drone lacks the S. basiconica and has far more S. placodea than the worker. The flagellum surfarce of the drone is twice as large as that of the worker and has 5 times as many sensory cells. The worker flagellum has a poreplate-free zone on the side facing the head which is densely packed with non-innervated setae. In the corresponding zone the drone has a lower density of poreplates than elsewhere on its antennal flagellum. All other sensilla and setae are also characteristically distributed.

Notizen: Summary The systematic position of the family Ochteridae is considered up to date as uncertain. Some authors claimed them to belong to the land bugs („Gymnocerata“), others to the water bugs („Hydrocorisae“). Skeleton and musculature of the head and prothorax ofOchterus marginatus Latreille have been investigated in order to clarify the systematic position. 1. The exoskeleton of theOchterus contains mainly plesiomorphic features as the long foursegmented rostrum, and the significant coxal cleft of the prothorax. Apomorphic features are the structure of the clypeus, the shortening of the antennae and the flattened side-flaps of the protergum. 2. The lack of the cranial apodemes of the antennal musculature and the broadened food pump which is endowed with epipharyngeal plates are pecularities of the endoskeleton. The sacks of the maxillary plates are medio-ventrally elongated in compact lobes, which reach distally as far as the hypopharynx. 3. Mandibular stylet and maxillary stylet possess levers. The mandibular lever is a flat and approximately triangular plate; the maxillary lever is a bent sclerit in the form of a stick. Both are derivates of double membranes. 4. The musculature of the head ofOchterus diverges only insignificantly from that of other bugs. a) There is also a musculus depressor labii primus posterior (KM 2b) which is used to move the long rostrum. This is either an independent muscle or part of the more frontally located KM 2a. The same development is found in the Saldidae and is therefore plesiomorphic. b) Musculus transversalis labii tertius (KM 6) of the third labial segment is strongly split into singular muscle strands. c) The mandibular stylet possesses 2 protractors and 2 retractors. 5. The head musculature and the mandibular and maxillary levers of the Cryptocerata are compared, and it is stated that a judgement of the conditions as found in the range of the stylets is only possible under consideration of the conditions among the „Gymnocerata“ and the „Homoptera“. 6. In the prothorax the following features of the musculature are remarkable: a) Development of two musculi proepisterno-postoccipitales (TM 10a, TM 10b). b) Splitting of the musculus noto-trochanteralis into two portions (TM 20a, TM 20b). c) Existence of a musculus noto-pleuralis (TM 11). d) Lack of the musculus coxo-trochanteralis (TM 21). 7. The comparison of the musculature of the pro thorax of the „Gymnocerata“ and the „Homoptera“ with the musculature ofOchtems yielded the following results: a) TM 10a and TM 10b are two muscles. They are found both in the „Homoptera“ and in the other bugs and thus belong to the basic elements of the prothorax of bugs. b) TM 11 is only found inOchterus andNotonecta. It seems however also existing inAphis andAleurodes and therefore belongs already to the groundplan of the Heteroptera too. c) The splitting of the TM 20 is an apomorphic condition. 8. The musculature of the stylets and the mandibular and maxillary levers of the bugs and of the „Homoptera“ are compared with each other. Consequently the following features belong to the groundplan of the Heteroptera: a) Maxillary levers. b) Flattened and approximately triangular mandibular levers which are attached to the mandibular sack without sinew. c) Two protractors of the mandibula. d) Two retractors of the mandibula. 9. Taking the discovered features into consideration the Heteroptera are divided into three groups: 1. Cryptocerata + Saldoidea; 2. Amphibiocorisae; 3. „Gymnocerata“ without Saldoidea and Amphibiocorisae. The Cryptocerata and Saldoidea are plesiomorphic in the development of the musculature of the stylets and the levers, whereas the Cryptocerata are proved to be a monophyletic group by other features. There are no common apomorphic features found for the groups belonging to the Saldoidea. The Amphibiocorisae and „Saldoidea“ are, however, possibly sistergroups, yet there are no positive arguments to link them to one of the other groups of the Heteroptera. 10. The long rostrum of the Saldidae and the Ochteridae is a plesiomorphic feature, both groups show also plesiomorphic conditions in the musculature of the stylets and in the mandibular and maxillary levers. Both families belong to different groups of the Heteroptera but they are similar in their carnivorous or necrophagous habits. The basic group of the Heteroptera therefore was probably zoophagous as well. 11. A diagram of the relationships of the Crytocerata is set up. According to this the Ochteridae are the sistergroup of the Gelastocoridae (Ochteridae + Gelastocoridae form the Telmatobia). The Telmatobia + Corixoidea + Aphelocheiroidea + Naucoroidea + Notonectoidea are proved as a monophyletic unit through the apomorphic development of the clypeus and the foodpump. They are the sistergroup of the Nepoidea.

Notizen: Summary 1. The paper deals with the comparative anatomy of the roof of the genital chamber in Mecoptera. Selected members of the order were used for the investigation. The following items are considered as the most important results. 2. A medigynium has been found in the following families: Nannochoristidae, Choristidae, Apteropanorpidae, Panorpodidae, Panorpidae and Notiothaumidae. 3. In the Nannochoristidae the mediygnium is considerably more primitive than it is in the other families of the Mecoptera. This allows the assumption of a similar configuration in the “basic plan” of the Mecoptera. 4. The Apteropanorpidae are in regard to the medigynium intermediate between the primitive Nannochoristidae and the extremely specialized Panorpidae. 5. The medigynium of the Mecoptera is thought to be a new achievement of the roof of the genital chamber. 6. An essential participation of the orthopteroid ovipositor in the construction of the medigynium is considered to be less probable. At best it could be imagined that remnants of the ovipositor have been preserved as the tongue-shaped processes (lamnae) of the Panorpidae-medigynium after having passed through a sternite-like stage.

Notizen: Summary 1. Aiming towards a better understanding of the functional role played by the arrangement of slit sense organs in the exoskeleton of arachnids the diversity of their topography is studied in the walking leg. Data previously collected with a spider and a scorpion are supplemented by such on a whip spider, a whip scorpion, and a harvestman. Thus five arachnid orders are now available for the comparison. 2. There is a wide spectrum of both the richness in total slit sensillar supply and the relative share contributed to it by isolated slits, groups of single slits, and lyriform organs, respectively. Whereas lyriform organs are numerous on the spider leg (15) none or only one or two occur in the other arachnids. On the leg of the scorpion and whip scorpion one instead finds an almost equivalent number of groups at comparable sites (12, 13). Whip spider and harvestman clearly have the smallest number of slits on their legs with 58 and 45 as compared to the 325 of the spider leg. 3. An outstanding feature of all the arachnid legs studied is a concentration of the slits proximally on the leg. This is most pronounced in the harvestman and whip spider, i.e. those cases with the smallest total number of slits (percentage proximal to tibia: spider 70%; harvestman 100%; whip spider 93%). The trochanter is the leg segment most richly supplied. A location right at or close to the distal end of the respective leg segment (i.e. to proximal part of articulation) is a typical though not general property of lyriform organs and groups, but not of isolated slits. 4. A position laterally on the leg close to a joint and an orientation of the slits roughly parallel to the long leg axis is common among both lyriform organs and groups. The harvestman has the least conformistic leg with the groups oriented more or less perpendicular to the long leg axis. Slits in the most ventral region of the leg are very rare. The femora of the harvestman, whip scorpion, and whip spider bear some large isolated slits oriented perpendicular to the long leg axis, which is exceptional. Within some lyriform organs and groups (see f.i. trochanter of whip spider) the axes of the constituent slits divert. 5. These morphological findings are discussed in terms of their physiological significance. The arguments put forth are relevant for an understanding of the topography of campaniform sensilla on the insect leg as well.

Notizen: Summary The cnidosac has been investigated in 14 species of Aeolidoidea from the Gulf of Naples and from Roscoff with the light microscope and in one species,Cratena peregrina, with the electron microscope. The morphology of the entodermal cnidosac is similar in all species. The cnidosac is more or less an ellipsoid or spindle shaped organ, which is connected with an open pore or a narrow duct with the hepatopancreas — and which is always closed at its distal end. A permanent, epithelial cnidopore was not observed. The single-layered epithelium of the cnidosac is mainly composed of nematophages (= cnidophages). At the entrance of the cnidosac and at its distal end there often occurs a zone of undifferentiated cells, believed to serve for regeneration of lost cnidophages. The cnidophages phagocytize cnidocysts (nematocysts) and may store it for a long time. The nematocyst and the nematophag remain intact, whereas the nematocyt always becomes digested. The nematophages are characterized by large mitochondria, large golgi complexes, by a basal labyrinth, an active nucleus with a large nucleolus and by vacuoles containing tubular bodies. Pericaryell, a week rough endoplasmic reticulum, is found while in the apical cell region the endoplasmic reticulum is smooth and appears “empty”. The nematocysts possess an intact fine structure and lie within a vacuole. The unit membrane of the vacuole encloses the nematocyst very closely. The arrangement of the cnidocysts within the cnidophages is species-specific, p.e. the nematocysts lie parallel to one another inAeolodia papillosa, while they are arranged in a “circle” inTrinchesia ilonae or like a bouquet inTrinchesia granosa. Within the cnidophage the cnidocysts are stored unexploded and remain functional for a long time. Many species store only certain types of nematocysts of the cnidom of the hydroid. The mechanism of this selection is unknown. When the nematocysts are ejected the epidermis and the epithelium of the cnidosac burst at a preformed zone. This region is characterized by being very high and slender, but otherwise “normal” epidermal cells and often by undifferentiated nematophages. Muscles are absent in this region. The nematocysts are ejected within the nematophages. The cell membrane bursts only in the sea water and the cnidocysts explode. The cleft is closed by contraction, which bring the epidermal cells of the wound border and the undifferentiated cells of the cnidosac epithelium close together. The nematocysts are usually ejected only on appropriate violent mechanical stimulation. A slow, continuous ejection lasting for several days or a spontanuous, repeated ejection as a natural modus of excretion have never been observed.

Notizen: Summary The simple pharynges in thirteen species of Turbellaria in the orders Macrostomida, Haplopharyngida, Catenulida, and Acoela have been studied by electron microscopy. After consideration of the functional aspects of the pharynx simplex, the relationship of the pharynx simplex ultrastructure to the phylogeny of the above mentioned groups is analyzed. The Haplopharyngida and Macrostomida are united as a group by the following characters: a pharynx transition zone of 1–5 circles of insunk cells with modified ciliary rootlets or no cilia, pharynx sensory cells without stereocilia collars and with a variable number of cilia, a prominent nerve ring with more than 30 axons circling the pharynx at the level of the beginning of the pharynx proper distal to the gland ring, 2 or more gland cell types in the pharynx, with at least two layers of muscle present and the longitudinal muscles derived from regular and special body wall circular muscles and a prominent post-oral nerve commissure. This specific arrangement can be distinguished from the other pharynx simplex types and is called the pharynx simplex coronatus. The catenulid pharynx simplex is characterized by the lack of a prominent nerve ring, no prominent post-oral commissure, a transition zone with epidermal type ciliary rootlets, recessed monociliated sensory cells, and one or no type of pharynx gland cell. The Acoela are specialized because of the epidermal type rootlets in the pharynx proper. They also lack a transition zone and a prominent nerve ring and have monociliated sensory cells different from the catenulid type. Ultrastructural characters of the pharynx simplex support the view that the Haplopharyngida-Macrostomida are monophyletic. The more primitive catenulid pharynx probably arose from a common ancestral pool with the Haplopharyngida and Macrostomida, although it does not appear possible presently to establish a clear monophyletic line for these forms. The various pharynx types within the Acoela appear to indicate independent origins with no clear link to the basic pharynx simplex type in the three other orders.

Notizen: Summary The surface anatomy and the structures lining the pharynx of Halicryptus spinulosus were examined by scanning electron microscopy (SEM). The structures were compared and contrasted with those reported for other priapulids, particularly those features previously studied with SEM. Buccal papillae and pharyngeal teeth of two types were described. Surface structures observed with SEM were: scalids, abdominal setae, anal papillae, posterior warts and ring papillae. The latter three structures are unique among described priapulids. The anal papillae are composed of several rounded, perhaps pedunculate, structures; the posterior warts are composed of mitriform structures in close association with columnar structures. Both are located in separate depressions in the posterior integument. The ring papillae occur on the annuli close to the posterior end. Halicryptus spinulosus was previously thought to lack these structures.

Notizen: Summary The ultrastructure of the blood vessels in the caudal region of Branchiostoma is described in specimens injected with indian ink. None of the vessels have endothelial cells delimiting the luminal surface. The vessels are delimited either by dense connective tissue or by the characteristic basement lamella underneath the basal lamina of the myocoelic epithelium. It is proposed that the main blood flow in the caudal region follows different pathways depending on the activity of the animal. During swimming the muscle activity of the caudal muscles may have the effect that more blood flows from the aorta to the myoseptal plexi and is drained to the caudal vessel. In the resting animal it is possible that the blood flow through the myosepta is insignificant, and that the caudal blood flow is more or less restricted to the direct connections between the aorta and the caudal vessel: the dorsoventral anastomosis and the segmental connecting vessels.

Notizen: Summary The flagellated chambers of Ephydatia fluviatilis arise at scattered sites within the mesenchyme. Each such site is marked by an accumulation of rounded cells, which appear to be derived from archaeocytes in most respects except that they are smaller than the latter and have no nucleoli in the nucleus. These are choanoblasts, which first develop a flagellum and later a collar; eventually, as choanocytes, they become arranged so as to form a flagellated chamber. Having reached this preliminary stage of completion in the mesenchyme, the flagellated chambers migrate to the endopinacocyte epithelium of the excurrent canal system. Then the choanocytes at the contact point are converted to cone cells. The endopinacocyte epithelium in turn responds by developing one pore cell for each flagellated chamber. The porocytes become permanently joined to the chamber by way of the adjacent cone cells, and from this time on the flagellated chamber is functional.

Notizen: Summary Observations on two species of sponges, Tethya seychellensis from the Red Sea, and T. aurantium from the Mediterranean Sea revealed that young colonies are able to detach from their sites of settlement and by means of filamentous podia, to move to other sites in the vicinity. These podia are 10–16 mm long extensions of the sponge body wall that bear an adhesive knob on their distal ends. After being attached, the contracting ‘podia’ pull the spherical colonies of 2.0–3.0 cm in diameter, transporting them to a new site. EM observations showed that in the podia the matrix is rich in contractile myocytes, primary archaeocytes, nucleated archaeocytes and scleroblastic cells, each of which takes part in the moving ability of the podium. It was also shown that some of the archaeocytes go over a process of ripening within the podium and produce collagenic filaments deposited in the internal matrix.

Notizen: Summary The position of the oocyte nucleus within the ooplasm is fixed during the mid and late stages of house fly oogenesis. The germinal vesicle is located near the border of the nurse chamber, towards the periphery of the oocyte. The position of the anlage of the chorion raphe is strictly related to the germinal vesicle. As the raphe corresponds to the dorsal side of the later embryo, both the position of the oocyte nucleus and the raphe anlage in the follicular epithelium are early indicators of the dorsoventral axis of the house fly egg cell. In cross sections of the ovary the follicles are arranged in several concentric circles. The dorsal sides of all follicles within the ovary are oriented to an imaginary center. This center of orientation lies eccentrically near the medial part of the female abdomen. The resulting symmetrical pattern can be observed throughout the course of oogenesis. This implies that only a few follicles have the same dorsoventral orientation as the mother fly, and therefore this arrangement is contradictory to the imprinting hypotheses of body axis formation as well as to a possible inductive role of gravity.

Notizen: Summary Histological and ultrastructural observations of the digestive tract of eight-armed plutei of Dendraster excentricus are reported. The esophagus is divided into two regions. The uppermost is a narrow tube comprised of ciliated cells that assist in transporting food to the more bulbous lower esophagus where food particles are formed into a bolus prior to entering the stomach. The esophagus is surrounded by a network of smooth muscle fibers that are predominantly oriented circumferentially in the upper esophagus, and longitudinally in the lower esophagus. The musculature of the upper esophagus produces peristaltic contractions, whereas contractions of the muscle of the lower esophagus open the cardiac sphincter and force food from the lower esophagus into the stomach. Axons are associated with the ciliated cells and the muscles of the upper esophagus. The cardiac sphincter consists of a ring of myoepithelium, with cross-striated myofibrils oriented around the bases of the cells. The gastric epithelium is comprised of two cell types. Type I cells, which predominate, absorb and store nutrients, and may be the source of secreted digestive enzymes. Type II cells apparently phagocytize and intracellularly digest whole algal cells. The intestine is comprised of relatively unspecialized cells and probably functions primarily as a conductive tube for the elimination of undigested materials.

Notizen: Summary Spermatogenesis was studied at the ultrastructural level in Polydora ligni, P. websteri, P. socialis and Streblospio benedicti. Spermatogonia, spermatocytes, spermatids and mature sperm are described. In all four species, meiosis occurs in the coelom following release of spermatogonia from the gonad. In Polydora spp., chromatin condensation is lamellar with no microtubules present during nuclear elongation. In S. benedicti, chromatin condensation is fibrous with a manchette of microtubules present around the nucleus. In all four species, the acrosome forms from a Golgi-derived vesicle situated at the base of spermatids. The acrosome in Polydora spp. is conical with a distinctive substructure whereas the S. benedicti acrosome is long and spiral. The implantation fossa is short in all species except P. ligni. All four species have elongated sperm heads. The middlepiece as well as the nucleus is elongated in Polydora spp. whereas S. benedicti has a long nucleus but a short middlepiece. Platelet-shaped electron-dense bodies are present throughout the nuclear region and middlepiece of Polydora spp. and the nuclear region of S. benedicti. These membrane-bounded bodies may be energy storage organelles. The use of ultrastructural data in analysis of sibling species complexes is discussed.

Notizen: Summary Ototyphlonemertes pallida (Keferstein, 1862) has two statocysts, which are situated just behind the dorsal ganglions on the elongations of the ventral ganglions. Each statocyst consists of one statolith chamber cell, some nerve cells and a number of covering cells and is surrounded by a thick basement membrane. Usually the statolith chamber cell encloses three statolith chambers, which are intercommunicated and surrounded by a double membrane. Each chamber contains a single mobile statolith. Cilia and ciliary structures are lacking. Within the dorsal part of the statocyst some very ramified nerve cells are situated, which form a nerve fibre. In the vicinity of the statolith chamber cell the nerve cells split up into synaptical plates with electric synapses; there are one or several synaptical plates at the level of each chamber. The statolith chamber cell is surrounded by numerous covering cells, which are connected by desmosomes and additionally linked together at the outside in the ventral part of the statocyst. With regard to their structure the covering cells differ greatly from the other cell types, and they do not participate in impulse perception and impulse conduction. There do not exist any closer morphological relations to the statocysts lacking cilia in Coelenterates, Turbellaria, Holothuria, Xenoturbella and Tunicata. The statocyst of O. pallida represents an indigenous structure within the Nemerteans.

Notizen: Summary The pericardium in Lepidopleurus asellus (Spengler), Tonicella marmorea (Fabricius), T. rubra L., Ischnochiton albus L., and Calleochiton laevis (Montagu), species taxonomically far apart, is described. It consists of a flat, simple epithelium facing the pericardial cavity, a basement membrane, a muscle layer with two types of muscle fibres, nerve processes, glio-interstitial cells, and fibrocytes, embedded in a loose collagen matrix. The epithelium in L. asellus and I. albus have convoluted lateral cell borders, and in L. asellus very long basal cell processes are seen. Type 1 muscle fibres resemble smooth molluscan muscle. Type 2 muscle fibres resemble cardiac muscle fibres in chitons. Nerve processes associated with glio-interstitial cells and cell processes, run free in the matrix. Synapses in type 1 fibres are covered with glio-interstitial cell processes, lacking in type 2 muscle fibres synapses.

Notizen: Summary Dart formation in Helix aspersa has been investigated by SEM of isolated darts at progressive stages in their development, and by histology of dart sacs at the same times. Dart formation begins at the tip of a tubercle where a small group of epithelial cells secrete an organic material filling a small CaCO3 cone that is the first mineralized part of the shaft. Subsequent secretory activity by an increasing area of the tubercle epithelium results in an increase in the diameter and anterior lengthening of the shaft. Continued secretion by the tubercle and dart sac epithelium produces the flare and finally the corona. A pattern of deposition is also evident in the fine structure of the mineral. In the shaft and vanes there is an inner layer of spherulitic prismatic structure which is covered by a layer of irregular patches of simple prismatic structure. The outermost layer of the shaft and vanes has a continuous simple prismatic structure. Two layers are present in the flare, an inner granular amorphous layer and an outer spherulitic prismatic layer. The corona consists of a single rarefied prismatic layer. A mechanism of dart formation is suggested that involves two types of organic matrix, calcifying and non-calcifying. Measurements of the calcium content of darts, dart sacs, and collars indicate that the hemolymph is the probable source of calcium for the dart.

Notizen: Summary Primordial gemmules in the freshwater sponge Ephydatia fluviatilis consist of archaeocytes, trophocytes, and spongioblasts. Once the shell has been completed the gemmules contain only archaeocytes filled with food reserves; they become binucleate before completion of the shell. The three layers of the gemmule shell discernible in the light microscope — the inner, vacuolar, and outer layers — are secreted by a highly prismatic spongioblast epithelium along a gradient from the apex to the base of the sponge. All the evidence indicates that these spongioblasts are temporarily modified exopinacocytes. Shell formation is initiated when a group of flat archaeocytes at the periphery of the inner cell complex assumes the function of establishing the shape of the shell. That is, they secrete toward the spongioblast epithelium a boundary layer, detectable only electron microscopically, that marks the inner surface of the shell. Each of the microscleres (amphidisks) in the gemmule shell is formed within an amphidiskoblast in the mesenchyme; when auxiliary cells have contacted the amphidiskoblast, they move together to the spongioblast epithelium in a region of the shell. There the spicule is released from the cell complex and incorporated into the shell. The membrane that closes the pore (micropyle) of the gemmule shell is secreted by a group of modified spongioblasts (micropyle spongioblasts). It consists of a continuation of the inner boundary layer lining the shell itself, detectable only electron microscopically, plus two other layers not identical with any layer of the shell. Toward the end of shell formation the spongioblasts flatten, creating a permanent pavement epithelium that secretes a thin envelope of spongin over the surface of the completed gemmule.

Notizen: Summary The effect of alkaline hydrogen peroxide on Douglas fir sapwood and heartwood was investigated by ultraviolet microscopy and reflectance spectrophotometry. It was found that the high absorbance of the heartwood elements around 300 nm which was attributed to the flavanone dihydroquercetin was readily eliminated by the action of peroxide. It is also proposed that the brightening effect of hydrogen peroxide is due in part to the destruction of coniferaldehyde groups which occurs to the same extent in both sapwood and heartwood and in all the morphological elements. A correlation between the concentration of chromophoric groups and the concentration of lignin is demonstrated.

Notizen: Summary White spruce (Picea glauca) was treated with ammoniacal solutions of various preservatives containing copper, zinc, and arsenic. The wood was then leached in a severe accelerated test and the amount of copper, zinc, and arsenic lost from the wood was determined. The leachability of arsenic depended on the preservative formulation; when the ratio of metal oxide to arsenic oxide was less than 1.25, 35 to 67% of the arsenic was lost, but when this ratio was greater than 1.25 only 1 to 15% of the arsenic was lost. Only small amounts (1 to 4%) of copper and zinc were leached out using any of the tested formulations. Temperature of fixation had only a slight influence on leaching of copper, zinc or arsenic.

Notizen: Summary Aim of this study is to determine the basic equations concerning the second boundary value problem of the theory of elasticity in particular for construction wood. For rhombic orthotropic materials, as represented for example by straight grained wooden constructions, the equations are calculated in Cartesian co-ordinates. For cylindrical orthotropic materials, as represented for example by curved laminated beams, the equations are calculated in cylindrical co-ordinates. In both cases the equations are determined for space stress problems. Assuming the plain stress condition the basic equations of plain stress problems can then be derived from the spatial equations.

Notizen: Summary Measurement of the potential deformations contained in standing trees, induced by growth stresses were made using an extensiometric technique which is described. The same extensiometric transducers and methods were also used to evaluate the elastic mechanical properties of green wood necessary to transpose the numeric values of longitudinal microdeformations into mechanical stresses. Measurements were made on 86 different beech trees located in the principal regions of France. The data obtained not only established the feasibility of the method but permitted an objective numeric evaluation of the level of potential deformations found at the base of individual trees. The results could be correlated with the forest environment and also certain morphological and anatomical anomalies within the trees.

Notizen: Abstract The longitudinal unsteady-state flow of compressible fluids in wood is modeled on a basis of series elements of differing permeabilities and three zones acting in parallel. Two of these zones having widely differing permeabilities are capable of varying degrees of intermixing while a third low-permeability zone is isolated from the other two. A good agreement between theoretical and experimental results was achieved by the appropriate selection of the parameters.

Notizen: Summary Orifice flow and drag theory are found theoretically to be generally inapplicable to axial gas flow through conifer wood under the conditions normally used for gas permeability studies of the material. However, orifice flow theory might be applicable at higher mean pressures or at higher applied pressure drops. Methods of testing this possibility experimentally are discussed.

Notizen: Summary The maximum torsional-shear stress of 5 softwoods and 4 hardwoods were tested in the radial and tangential planes. These tests were carried out in glycerin which was preheated to different temperatures between 22°C and 150°C, inclusively. The dense hardwoods possess 2.4 times higher shear stress than softwoods at 22°C. However, at elevated temperatures, the same degree of shear stress reduction (77 %) is obtained for hardwoods and softwoods in both radial and tangential failure. Thus, the reduction in shear stress is independent of physical and structural wood variables.

Notizen: Summary Past research on the combustion and pyrolysis of wood have often indicated a link between wood microstructure and its observed properties in fire exposure. The present research, after utilizing an instrumented fire exposure shown to simulate actual fire conditions, examines the microstructure of fire damaged wood and considers the implications of microstructural changes seen on the burning process. Differences in microstructural detail between wood and char, as well as fissure geometry, were shown to be consistent. The demarcation between damaged and undamaged wood was shown to be extremely small (several cell layers in thickness). The resulting microstructural observations are considered in light of published kinetic data on wood combustion and current theories and data on thermal degradation of wood.

Notizen: Summary Radial pattern of variation in the first-formed earlywood tracheid length in blue pine shows that it increases outwards from the pith at first rapidly up to the 10th ring, then more slowly up to about the 40th ring and thereafter it remains more or less constant. It is correlated significantly and positively with both age and distance from the pith up to 40 years. In the mature wood zone i.e. after 40 years, tracheid length is not affected by either age or distance from the pith. The mean tracheid length of mature wood is significantly and positively correlated with the mean tracheid length of juvenile wood and also with the tracheid length of each of the juvenile wood rings. Based on the results of this study some guidelines for sampling are proposed. Trees with greater than 51 cm d.b.h. or above 40 years of age can be compared by sampling only four outermost consecutive mature wood annual rings; and those with less than 51 cm d.b.h. or below 40 years of age can be compared by sampling any of the juvenile wood rings.

Notizen: Summary Crosslinking of wood with gaseous formaldehyde improves its hygroscopic and dimensional behaviour and its resistance against microorganisms. However, this formaldehyde crosslinking reaction takes place only in the presence of an acid catalyst, which results in losses in mechanical strength. Electron microscopic analysis of poplar samples treated under various conditions of reaction revealed severe degradation of cell wall substances. The formaldehyde gaseous nonomer is shown to have some hydrolytic action on cellular structure. Sulphur dioxide and particularly hydrochloric acid used as catalysts caused substantial extraction of matrix substances from fibre walls. Walls of vessels and ray parenchyma cells seemed to become less degraded. Strong exposure of cellulose fibrils during formaldehyde crosslinking reactions, illustrated by highly electron transparent zones in the S1 and inner S2 layers, occurred for both the SO2 and HCl catalyzed treatments. In general a more extensive degradation was observed for the formaldehyde-hydrochloric acid reaction and for the formaldehyde sulfur dioxide treatments using a high acid concentration. From these observations it might be concluded that the reduced mechanical strength of formaldehyde-treated woods are partially based on the hydrolysis of the carbohydrate backbone of the cell wall.

Notizen: Summary The structure of the non-cyclic benzyl aryl (α-0-4) ethers 4 and 5, proposed by Freudenberg and Friedmann (1960) and recently boubted by Leary (1980), is discussed on the basis of previously published experimental results. Further evidence in favor of the occurrence of non-cyclic α-0-4 bonds in lignin is provided. A critical comment is, however, given on the formation of non-cyclic α-0-γ bonds in lignin according to Leary (1980).

Notizen: Summary As in all skarks, the ectoderm ofHeterodontus folds in behind the jaw cartilage during embryogenesis. The anterior part of this ectodermal fold becomes organized into the Inner Enamel Epithelium which cooperates with the mesenchyme. Already during the infolding, both tissues begin to form teeth. This process begins with a spontaneous division of the fold along its long axis into tooth-forming and non tooth-forming tissue sections. In this way the tooth formula of the “first dentition” is established. The Inner Enamel Epithelium and the mesenchyme only gradually attain competence for tooth formation, so that the first formed tooth germs become incomplete tooth shards (Fig. 8). Shortly before the end of the embryonic phase, as soon as the infolding stops, the tooth transport mechanism begins to work.Heterodontus hatches with a characteristic “first dentition”, which has a typical dental formula of 17to19/13to15. Because of allometric growth, the number of tooth families increases strongly in the course of a lifetime, but to different degrees in the various species. The “first dentition” is composed of teeth having numerous needle-like cusps; it is only slightly heterodont and serves in feeding on soft-bodied benthonic animals. In the course of ontogeny, a highly heterodont dentition becomes differentiated. The anterior part of the adult dentition is composed of teeth with 1–3 cusps, while the distal part bears molariform teeth. On the basis of these distal teeth, two groups of species may be distinguished: a primitive group (Francisci-type) distributed in the Indopacific and having slender, keeled crushing teeth (probably specialized for a diet of echinoderms), and a group of species derived from it (Portusjacksoni-type) found only in the western Pacific and having broad, powerful crushing teeth capable of cracking hardshelled molluscs. It is characteristic that the most distal tooth family of the first dentition becomes the main crushing tooth within the molariform group in the course of ontogeny. This tooth family lies at the point where the most force can be brought to bear by the jaw apparatus, and remains there life-long; that is, it does not change position relative to the jaw. Since the infolded ectoderm lies on the inner side of the jaw, its growth is controlled by the growth of the jaw. The jaw on the Portusjacksoni-type grows forward sharply to form a beak so that the infolded ectoderm must grow forward with it and thus can form extra tooth families. The infolded ectoderm expands outwards in the course of ontogeny toward the distal ends of the rami. As soon as a gap appears between tooth primordia in this fold, it is filled by a new tooth germ whether the gap results from forward migration of an already-formed tooth or from elongation of the folded ectoderm during growth. In theHeterodontus dentition there are two tooth-form gradients: On one hand, tooth-form in each family changes in the course of time; on the other, the dentition is heterodont at each ontogenetic stage. Thus, within each dentition there is a tooth form and tooth size gradient. Tooth form and size, therefore, are determined by two coordinate parameters: 1. the age of the animal and 2. the position in the dentition. The observations on the dentition ofHeterodontus lead to the interpretation that the insertion of new teeth and tooth families, as well as their form and size, is regulated by a complex system of reference points which transmit positional information to the tooth-forming cells.

Notizen: Summary During the period between apolysis and ecdysis, the vesicular glands show many important transformations which affect not only the cuticular ductules, but all the cells. The cytoplasm of the glandular cells undergoes a partial autolysis, whereas other parts of the cells present a high secretory activity. Immediately after the apolysis the cellular reservoir empties and disappears almost completely; soon after, refills with secretion. The most interesting transformations concern each ciliary cell, always associated with a glandular cell. In the first phase of the moulting cycle, the dendrite of the ciliary cell grows a ciliumlike extension (= distal region of the dendrite), which penetrates into the corresponding ductule; the new intima of this ductule is laid around the cilium. At the same time, the proximal region of the dendrite forms a circular fold around the base of the cilium and begins to secrete a material which will form the end apparatus. This latter is finished during the second phase of the cycle. The third phase is characterized by the degeneration of the distal region of the dendrite and the circular fold. Thus, the end apparatus is not a secretion of the ductule-carrying cell, but of the ciliary cell. At the end of the moulting period, just before ecdysis, the vesicular gland again takes the structure characteristic of the intermoult: the reservoir of the glandular cell is very large; the cuticular apparatus is almost formed; the dendrite of the ciliary cells shows, at its apex, a short “cilium” (= ciliary region s. str. + short distal region) surrounded by microvilli, free in the secretion of the reservoir.

Notizen: Summary Retinal adaptations to a tide pool environment in ten species of fishes belonging to as many families were studied. These fishes may be grouped into typical or temporary tide pool inhabitants. The retinal structure of these forms may be grouped into three categories viz. 1. visually dependent (good acuity and sensitivity), 2. specialised for dim environments (high sensitivity at the cost of acuity), and 3. poor visual ability.

Notizen: Summary 1. According to previous results of experiments concerning pulmonates the inferior epithelium of the radular gland has been found responsible for the continuous and mouthwards directed transport of new radular teeth. The motion of the epithelial cells, also directed towards the mouth, provides for the carriage. The structural basis of the transport mechanism is thus recorded according to light and electron microscopical studies on the slugLimax flavus L. 2. Close to the collostylar hood the inferior epithelium secretes the subradular membrane which extends under the anterior part of the radula and consists of thin layers. Rupture artifacts reveal that this has a tough or rigid consistence and is connected both to the radular membrane, which lies above it as to the inferior epithelium. 3. In the posterior part of the radular gland the cells of the inferior epithelium show a plane, thickly matted edge of microvillis. Microvillis however lack the cells in the anterior part of the radular gland. From about the collostylar hood the cells are inter-locked with the subradular membrane by means of strong apical projections. 4. As a result of intensive interdigitation with the inferior epithelium the radula is carried at the same rate as the cells, underlying the subradular membrane move forward. Within the radular gland the radula most likely glides over the apical cell area.

Notizen: Summary The present study concerns the functional organization of the skin ofTetraodon fluviatilis. The epidermis consists of five different types of cells — the flask-shaped mucous cells, the eosinophilic granular cells, the sacciform granulated cells, the vesicle containing granulated cells, and the polygonal cells. A thin noncellular layer, the cuticle found on the surface of the skin, is probably secreted from the polygonal cells in the outermost layer of the epidermis. A,well-defined lymphatic plexus exists between the cells of the basal layer. Numerous triradiate calcareous spines are embedded within elastic connective tissue pockets in the thick dermis. These pockets are filled with an amorphous, acellular, PAS positive material, and are richly supplied with fine blood capillaries. A histomorphologic basis for the erection of the spines and various structural modifications in the skin facilitating its enormous stretching under inflated conditions of the fish are discussed.

Notizen: Summary The hair-plate sensilla of the honeybee were examined by SEM and TEM. Apart from the normal single bristles, some were found with a threepronged point. The dendrite runs eccentrically within the cuticular canal. Below the socket septum it is enveloped by sheath cells 1 and 2. Sheath cell 2 also lines the remaining part of the cuticular canal and the subcuticular cavity continuous with the canal lumen. From sheath cell 2, abundant lamellae project into the canal system. The lamellae seem to have a double-unit membrane with a somewhat granular appearance.

Notizen: Summary The vestibulum is very short and lined by stratified squamous epithelium which contains many “alveolar” cells. The cavum nasi proprium is exceedingly complex, with three conchal formations and a series of six recesses and sinuses. Olfactory epithelium lines the whole dorsal or dorso-medial half of the cavum, but not the deep sinuses. Non sensory respiratory epithelium lines the ventral or ventro-lateral half of the cavum, all the caviconchal recess, the posterolateral recess, the postturbinal sinus, the postconchal cavity, and the nasopharyngeal duct. In olfactory epithelium the proportion of sensory cells is about 61 % inCrocodylus and 59 % inCaiman; the ratio of sensory cells to supporting cells is about 2.6/1 in the former and 1.8/1 in the latter. Bowman's glands are sero-mucous and normally developed. As in other reptiles, the respiratory epithelium is composed with mucous and ciliated cells; but, in ventrolateral part of the cavum, there are also sero-mucous cells forming small multicellular glands. The hypertrophied lachrymal duct constitutes a very large naso-lachrymal not previously described gland. The lumen is lined by mucous and ciliated cells, the collet of each branched tubular gland by mucous cells and the glandular tubes by sero-mucous cells. Adult crocodilians lack a Jacobson's organ and there are no vomeronasal sensory epithelium in the cavum. In reptiles, aquatic way of life generally involves regression in olfactory epithelium, while Jacobson's organ (or, in Testudines, vomeronasal epithelium) persists and occasionally increases. In crocodilians, things are exactly reverse. After comparing with other Tetrapods, it seems likely that Jacobson's organ has been lost by terrestrial ancestor of crocodilians and birds. Now, only crocodilians posses olfactory epithelium, and naso-lachrymal gland gives them a supplementary protection, necessary in semiaquatic environment.

Notizen: Summary The ultrastructure of the male genital tract ofPeripatopsis moseleyi has been examined under the electron microscope. In the testes somatic cells, spermatogonia and spermatocytes occur. In the spermatocytes electron-dense granules are built by the Golgi-apparatus. They are released from the developing spermatid and can still be detected in the spermatophore. The spermiogenesis takes place in the seminal vesicles. Nuclear condensation and elongation, formation of middle piece and acrosome are described. The mature sperm cell has an elongated nucleus, a middle piece containing mitochondria only and a tail with 9+2-formation and accessory microtubule systems. The spermatophore is built within the vas deferens the epithelial cells of which secrete great amounts of material enveloping the sperm mass.

Notizen: Summary The epithelial cells of the honeybee midgut show aZonula continua (continuous junction) in the apical contact region. The cells of the regeneration krypts which do not border upon the gut lumen lack continuous junctions. AZonula continua is also differentiated in the Malpighian tubules. To make tight the intercellular space against penetration of macromolecules is discussed as a possible function of continuous junctions in resorbing epithelia.

Notizen: Summary The prothoracic skeleton ofAtractocerus (Lymexylonidae) is described. In the so-called precoxal bridge the anepisternum is separated by a suture which is recognized as anapleural suture. In the caudal part of the precoxal bridge a sternal plate (basisternum and furcasternum) is separated. The trochantinopleural plate is divided by a pleural suture in epimeron and katepisternum + trochantin. The connexion of trochantinopleura and tergum is only membranous. Specialized joint structures are absent in both sclerites. The cryptopleural invagination is not as much developed as in other Polyphaga. A fairly well sclerotized and large spinasternal plate exists. Two large laterospinae are present on both sides. In the cervical region a large dorsal cervical sclerite and two lateral cervical sclerites are to be found on both sides. Some structures are recognizable in the porthoracic region ofAtractocerus which have been lost in other Coleoptera (also in Adephaga and Cupedidae). Conditions as seenm Atractocerus are believed to be very primitive among Polyphaga. Hence it is supposed, that the original prothorax of Polyphaga has been very alike the neuropterian one in possessing a pleura, membranous over lager areas, the connexion of which to the tergum was not solid. The coxae are supposed to have been free distal being able to free movement. The most primitive polyphagous prothorax is believed to come very close to the generalized prothorax of the holometabolous insects. Concerning the primitiveness of the polyphagous prothorax the hypothesis of a sister-group relation of Coleoptera and the remaining Holometabola is discussed once more. The highly plesiomorphic status of the polyphagous prothorax as compared with the prothorax of Adephaga and Cupedidae is stressed. For this reason it is considered that Cupedidae and Adephaga might be more closely related to each other, than either to the Polyphaga. The position of the Myxophaga is discussed, but is not possible to decide at present. A closer relation of the Myxophaga to Adephaga and Cupedidae than to Polyphaga is taken into consideration. It is not shure at all, however, whether the Myxophaga constitute a monophyletic group.

Notizen: Summary A study of the copulation phases inBoreus westwoodi (Hagen) revealed that the tergal apophysis of the second and third abdominal segments, which are modified as the accessory copulatory organs of the wing rudiments, serve to grip the female. During the course of copulation, the male holds the female between his hook-like wing rudiments which clasp the base of her abdomen. The dorsally recurved male abdomen grips the female like a hook. In this process, the tergal apophyses keep pressing against the female abdomen so that the latter is prevented from slipping out backwards from the wing and abdominal clasping organs.

Notizen: Summary Light and dark adaptations were studied in the eye of Squilla mantis. Light adaptation is characterized by (1) a proximal shift of the distal pigment sheath (DPS) surrounding the proximal portion of the crystalline cone above its zone of contact with the rhabdom; (2) flattening of the distal pigment sheath; (3) lengthening of the crystalline cone correlated with shortening of the rhabdom; (4) a migration of screening pigment granules in retinula cells in the protoplasmic bridges crossing the perirhabdomal space. In animals kept in constant darkness, longitudinal displacements of the distal pigment sheath were found to be subject to a circadian rhythm characterized by a maximal light adaptation state at about 5 p.m. and a minimal one at 5 a.m. Screening pigment granule translocation in retinula cells does not show such rhythmic activity.

Notizen: Summary The male copulatory apparatus of Pelodera strongyloides is described using electron microscopical pictures. The genital structures are composed of a spicule, a spicule sac and a bursa copulatrix. Papillae of the bursa copulatrix, which are chemoreceptors, and papillae of the spicule sac and the spicule, which are mechanoreceptors, represent the sensory equipment. The co-operation of all structures during copulation is discussed.

Notizen: Summary The morphology and mechanics of the larynx and the ventral pharyngeal valves of the pigeon (Columba livia L.) are described. The glottal apparatus is an elastic ring of cartilage since the caudomedial ridges of the cricoid wings are tightly interconnected via the median cauda procricoidea. The bilateral arytaenoids can only hinge mediolaterad relative to the corpus procricoideus as a result of their particularly shaped articulation facets. The procricoid is tilted by changing the constriction of the ring. At rest, the glottis is held in an intermediate open position because the arytaenoids are kept along the dorsal ridges of the alae cricoideae in an ‘elastic open rest’ position by the elasticity of the ring and of the lig. arytaenocricoideum. The large dilator muscle covers the apparatus as a continuous sheet. The constrictor muscle complex, however, has five discrete sections, each having a different origin. They all insert on the heavy interarytaenoid ligament and one of them is a sphincter. These five sections can constrict the cricoprocricoid ring, thus causing a forward tilting of the procricoid which forces the arytaenoids to hinge mediad. The glottal apparatus operates as a drill-chuck system in which the arytaenoids are taken as the graspers (chuck jaws). The model is studied by a movement- and electromyographic analysis of three common glottal actions: respiration, reaction to water, and reaction to touch. The ‘elastic open rest’ position of the glottis is found in anaesthetized birds. The drill-chuck model is tested by the comparison of the recorded myogram pattern with the myogram pattern that must follow from the model for the moving structures. The ventral pharyngeal valves are erected by the long submucosal m. hyovalvularis, running between the basihyal and the dorsal side of the gland. cricoarytaenoidea in the valves. The valves are pulled down to the floor of the pharynx by a network of collagen and elastic fibres connected to the small m. tracheovalvularis, which runs down to a medium strand attached to the first tracheal ring. These two subsystems of the floor of the pharynx operate independently during respiration. But, in case of pecking and drinking they show combined actions which place them as parts of a highly integrated system.

Notizen: Summary The entire gut of Cyathura carinata is lined by a cuticle indicating its completely ectodermal origin. By flattening of the epithelial folds and possibly also of reserve-folds of the plasma membrane the intestine is highly dilatable, an adaptation towards a rapid uptake of the food which is sucked in by means of specialized mouthparts, which pierce the body wall of its main prey, the polychaete Nereis diversicolor. Bundles of microtubules within the intestinal cells presumably represent cytoskeletal structures providing protection against mechanical stress. Spirally arranged muscle fibres, which form peculiar contact areas with the gut, can easily follow any dilatation. A few indications of the metabolic functions of the anterior gut epithelium have been found: Basally and apically located labyrinthine structures of the plasma membrane, apically located clear vesicles, positive reactions for lysosomal, mitochondrial and membraneous enzymes, a strikingly thin and loosely arranged cuticle through which food substances of low molecular weight may diffuse. The cells of the gut and also of the digestive caeca are interconnected by desmosomes, extensive pleated septate junctions, and gap junctions. In the pleon the gut is less dilatable and devoid of plasma membrane specializations. In this area tendon cells, particularly rich in microtubules, serve as attachment sites for the dilating muscles of the rectum. The digestive caeca synthetize and secrete digestive enzymes, mix food and enzymes in their lumen, resorb food molecules, store lipids and glycogen. In the glandular epithelium small cells, rich in rough ER, and a majority of large cells, rich in lipid droplets, occur which, however, are interconnected by a series of morphologically intermediate cells. All cells bear an apical brush border, form a basal labyrinth and contain high to medium activities of acid phosphatase, nonspecific esterases, ATPase, and succinic dehydrogenase. The ER-rich cells are far less frequent than in the omnivorous or herbivorous isopods (Sphaeroma, Idothea, Asellidae, Oniscoidea).

Notizen: Summary About 1 s after appropriate stimulation, arms of Florometra serratissima break at articulations called syzygies that are specialized for autotomy. The fine structure of unreacted and of newly broken syzygies is described. The unreacted syzygy includes (1) ligament fibers consisting of collagen fibrils interconnected by interfibrillar strands and (2) axons filled with presumed neurosecretory granules. The newly broken syzygy includes (1) ruptured ligament fibers consisting of swollen collagen fibrils associated with interfibrillar globules and (2) axons containing few presumed neurosecretory granules, some of which are fixed in the act of exocytosis; moreover, the calcareous skeleton adjacent to the broken syzygy is partly eroded. The observations before and after breaking suggest that the autotomy mechanism may comprise the following sequence of events: rapid neural transmission from stimulation site to syzygy triggers a massive exocytosis of granules from presumed neurosecretory axons; the released neurosecretions (which could include chelating agents, strong acids, proteolytic enzymes or enzyme activators) etch the skeleton and lower the tensile strength of the ligament fibers by weakening the collagen fibrils and/or the interfibrillar material; breakage of the ligament fibers, the major connective tissue of the articulation, is quickly followed by rupture of all the other tissues at the syzygy.

Notizen: Abstract Water, sediment and microorganisms were sampled at stations along a trackline in the Atlantic Ocean off the North Carolina Coast (USA) at depths of 9 to 5,000 m. Selected chemical and physical parameters were measured. At three of the stations, microorganisms isolated from sediment were examined for ability to degrade a number of petroleum hydrocarbons. Media made up with seawater or salts solution supplemented with nitrate and phosphate were employed in the degradation studies; significant growth and hydrocarbon degradation was observed. Bacteria from sediment samples collected at a depth of 5,000 m showed greater growth and hydrocarbon degradation when cultured in a sea-water medium than in media made up with salts solution. Growth of bacteria in sediment samples collected at two stations was found to be suppressed in sea-water medium when a 1% (v/v) mixture of 19 different petroleum hydrocarbons was added. The hydrocarbon mixture was useful in determining the hydrocarbon degrading potential of microorganisms isolated from the ocean environment.

Notizen: Abstract The present investigation concerns the effects of calcium, strontium, and magnesium on calcification and mineralogy of the calcified bodies (coccoliths) of the coccolithophorid Cricosphaera (Hymenomonas) carterae. The capacity of cells to calcify in various concentrations of these ions was examined following preliminary decalcification in CO2. At a concentration of 10-2 M Ca, 75% of the cells formed coccoliths within 24 h and almost all cells were recalcified after 2 days. At 10-3 or 10-4 M Ca no recalcification occurred. However, with the addition of Sr to the Ca-deficient media, calcification took place as shown by observations of coccoliths and by analysis of Ca. The percentage of calcified cells increased with increasing concentrations of Sr. Strontium added to a Ca-deficient media was much more effective than an equivalent concentration of Ca. No Sr was deposited in the coccoliths. X-ray analysis demonstrated that calcite was deposited by cells in all concentrations of Ca and Sr at which calcification took place. At concentrations of Mg in the media from O. O to 4.2×10-2 M, the cells retained their ability to calcify, although calcification was markedly reduced in the absence of Mg. In low Mg concentrations (1.3×10-4 and 4.2×10-6 M), the coccoliths were 60% calcite and 40% aragonite, and in teh absence of Mg, only calcite was formed.

Notizen: Abstract Nitrate reductase activity in marine phytoplankton has been assayed on a Technicon AutoAnalyzer®. A description of the automation is given with details of the apparatus and procedure. Twenty samples an hour can be processed. The automated method has been compared with the manual method. The results are in good agreement; a correlation coefficient of 0.96 has been calculated from the data. The results of a study on the diurnal variation of nitrate reductase activity in a phytoplankton shipboard culture are presented.