摘要:

AbstractThe process of spermatogenesis inGolfingia ikedaiwas observed with electron microscope. Clusters of primary spermatocytes continued spermatogenesis while floating in the body fluid. No direct connections were found between the cells and no cytophore formation was observed. Preacrosomal vesicles were formed from small Golgi‐bodies just after the meiosis. Subacrosomal substances were aggregated just under the acrosomal vesicle in the middle stage of spermiogenesis and changed into fibrous structures in the completed spermatozoon. A peculiar annulus structure developed around the base of the flagellum. The phylogenetic position of this worm was also discussed in relation to the polychaetes and other worm

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01299.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractVal‐Sella, M. V., Sesso, A.1980. Morphometric evaluation of the number of gonadotrophic cells of the teleostRhamdia hilariiin the maturation, mature and spent stages of the gonadal cycle. (Department of General Physiology Institute of Biosciences and Laboratory of Molecular Pathology, Department of Pathology, Faculty of Medicine, University of S. Paulo, Brazil.) —Acta zool.(Stockh.) 61(3): 133–139.The numbers of vacuolated and non vacuolated gonadotrophic cells (GTH‐cells) were estimated by the method number II of Aherne (1967) in 6 μm sections. The total number of GTH‐cells (× 104) in the maturation, mature and spent stages were respectively: 43.3, 63.1 and 35.8. From these totals the number of cells (× 104) showing vacuolated cytoplasm were respectively: 18.1, 30.7 and 26.7. GTH‐cells showing very large vacuoles possessed cavities of the rough endoplasmic reticulum (RER) with the fantastic dimensions of several micrometers of diameter. The cytoplasm of non vacuolated GTH‐cells was almost completely filled with secretory granules. Contemporaneously with the decline in number of GTH‐cells, observed from the mature to the spent stages, there is a rise in the number (evaluated qualitatively) of

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01300.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractDemmel, U.1980. Die Halsäste des Nervus vagus beim Alpaka,Lama guanicoe pacos(Linné 1758). [The branches of the vagus nerve in the neck of Alpaka,Lama guanicoe pacos(Linné 1758).] (Anatomisches Institut der Universität Köln, Bundesrepublik Deutschland.) —Acta zool.(Stockh.) 61(3): 141–146.Dissections of two newborn and two adult alpacas have shown: that the trapezius musculature of either side is supplied by branches of seven cervical spinal nerves and not by the external ramus of truncus nervi accessorii as in mammals in general; that the nerves which innervate the inner laryngic muscles as well as the mucous membrane of the lower part of the larynx are given off from the main trunk of the vagus nerve just outside the jugular foramen; that a nerve corresponding to the n. laryngeus recurrens of other mammals is absent. It is concluded that the lack of recurvation of the inferior laryngic nerve and the absence of the spinal part of the accessory nerve are character states of tylopod arti

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01301.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractCouchman, J. R., King, P. E.1980. Ovariole sheath structure and its relationship with developing embryos in a parthenogenetic viviparous aphid. (Zoology Department, University College, Swansea, U.K.) —Acta zool.(Stockh.) 61(3): 147–155.The ovariole sheath of the viviparous parthenogenetic aphidBrevicoryne brassicaehas been the subject of an ultrastructural examination, particularly with regard to its relationship with embryos at various stages of ontogeny. The sheath is a unilaminar, squamous epithelial layer enclosing germarium and embryos, but does not have an intrinsic trophic role until the connection between the embryo and germarial trophocytes, in the form of the trophic cord, is lost. At this time there is a degree of thickening and an increase in the number of cell organelles with ultrastructural indications of metabolic activity, a situation paralleled in the embryonic serosa. There is also evidence that haemolymph components may have direct access to the embryos through intercellular spaces in the sheath. Intercellular junctions, microtubules and cell overlap in regions of the sheath adjacent to embryos at a more advanced state of development are all implicated in a mechanism which resists deformation, maintains sheath integrity and allows embryo passage. A tunica propria and microfilament bundles are absent in the ovariole sheath of this spec

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01302.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractPatzner, R. A.1980. Cyclical changes in weight and fat content of the liver and their relationship to reproduction in the hagfishEptatretus burgeri(Cyclostomata). (Zoological Institute, University of Salzburg, Austria and Misaki Marine Biological Station, University of Tokyo, Japan.) —Acta zool.(Stockh.) 61(3): 157–160.The changes in weight and fat content of the liver in the West Pacific hagfishEptatretus burgeriwere studied over a period of one year. The liver somatic index shows a high increase from the beginning of December until migration in deeper water in July. From the beginning of April to the end of August the difference between male and female liver somatic index is statistically significant. This fact is brought in connection with the production of vitellogenin in the female li

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01303.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractTheisen, B., Breucker, H., Zeiske, E., Melinkat, R.1980. Structure and development of the olfactory organ in the garfishBelone belone(L.) (Teleostei, Atheriniformes). (Institute of Comparative Anatomy, University of Copenhagen, Denmark; Anatomisches Institut, Universität Hamburg, and Zoologisches Institut und Zoologisches Museum, Universität Hamburg, Federal Republic of Germany.) —Acta zool.(Stockh.) 61(3): 161–170.The structure and development of the olfactory organ in the garfishBelone belone(L.) were studied by light and electron microscopy (SEM and TEM). The olfactory organ has the shape of an open groove with a protruding papilla. In embryos and early juveniles the groove is smooth and is provided with a continuous sensory epithelium. During ontogenesis the papilla develops and the composition of the epithelium is changed as areas of nonsensory epithelium appear and eventually separate the sensory epithelium into islets. In adults the sensory epithelium consists of supporting, basal, and two types of receptor cells, ciliated and microvillous. In juveniles also ciliated nonsensory cells are present. This difference can be correlated with differing locomotory habits of adults and juveniles. The receptor cilia show a 9 + 0 microtubular pattern while the nonsensory cilia have the general 9 + 2 pattern. Deviating dendritic endings were found and are considered an indication of ongoing cell dyn

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01304.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractSchlüter, U.1980. Ultrastruktur der Pyloruszähnchen zweier Tausendfüßler (Tachypodoiulus niger, Polydesmus angustus). [An ultrastructural study of the pyloric spines in two millipeds (Tachypodoiulus niger, Polydesmus angustus).] (Institut für Allgemeine und Spezielle Zoologie, Giessen, Bundesrepublik Deutschland.) —Acta zool.(Stockh.) 61(3): 171–178.In millipeds, two different types of cuticular spines are found in the pyloric chamber. In Tachypodoiulus niger they are of purely superficial nature without anchorage in the epithelium. This type is the most abundant in diplopods. Polydesmus angustus posesses pyloric spines, which are anchored in the epithelium. Each of the pylorus epithelial cells form a spine and is supposed to be in connection with longitudinal musculature. The function of these spines is to destroy the peritrophic membrane. In P. angustus they are also responsible for the transport of t

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01305.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractZapata, A., Carrato, A.1980. Ultrastructure of elasmobranch and teleost thrombocytes. (Departamento de Morfología Microscópica, Facultad de Biología, Universidad Complutense, Madrid, Spain.) —Acta zool.(Stockh.) 61 (3): 179–182.The ultrastructure of circulating thrombocytes ofRaja clavataandTorpedo marmorata(Elasmobranchs) andRutilus rutilusandGobio gobio(Teleosts) was described. In elasmobranchs, only one thrombocytic cell type was found, while teleosts presented two types. These cells contained microtubules and cytoplasmic granules, whose functional significance related to clotting processes is an

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01306.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

AbstractNiilonen, T.1980. Fine structure of the phaosomous photoreceptor in the larvae ofPolydora ligniWebster (Polychaeta: Spionidae). (Institute of Comparative Anatomy, Copenhagen, Denmark.) —Acta zool.(Stockh.) 61(3): 183–190.Phaosomes are described in detail for the first time from the Polychaeta. They were only found in the larvae, whereas serial sections of one sexually mature adult did not reveal any. The photoreceptors of the phaosomous type are placed between the medial and lateral pigmentcup eyes. The distal part of the cell is in direct contact with the epidermal surface, whereas the proximal part rests on a basement membrane. The largest diameter of the spherical cell is 10 μm. In the area immediately around the phaosome very few pigment‐granules are found. The body of the phaosome is dominated by the visual vacuole, which is totally occluded by numerous intertwining microvilli. The length of the microvilli is at least 5 μm. The cytoplasm around the visual vacuole is restricted to a narrow bordering zone. A presumed chemoreceptor is found in close association with the p

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1980.tb01307.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY