摘要:

AbstractThe macula sacculi and the macula lagenae of the herring,Clupea harengusL., were examined by light microscopy, the macula lagenae is large compared to what is normal among non‐ostariophysan fishes, the morphological polarization of the hair cells in the inferior maculae shows a pattern which is similar to that usually seen in teleost fishes. The fibres in the nerves supplying the macula sacculi and the macula lagenae were counted and their diameters measured. The ramulus saccularis is divided in two separate ramuli innervating populations of hair cells with different morphological polarization. The saccular rostral nerve trunk contains 1800–2300 fibres, with 1300–1800 fibres in the caudal nerve trunk. The lagenar nerve is composed of 2100–4000 fibres. The fibre diameters are 1–14 μm in all ramuli. Silver staining of the nerve axoplasm reveals a unique differentiation of the maculae, which can be divided into a central area surrounded by a peripheral part. The hair cells in the central area are innervated by thick nerve fibres (5–14 μm diameter) as well as a few thin nerve fibres (about 1 μm diameter), while the receptor cells in the peripheral area are exclusively innervated by thin fibres having diameters o

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00810.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractNuclei associated with membranes lining the body cavity inPriapulus caudatusare shown by electron microscopy to be the nuclei of amoebocytes. The membranes themselves are not cellular and do not constitute a peritoneum. Mesenteries, present in the body cavity, also are not cellular; amoebocytes occasionally are found within them. These findings weaken the idea that priapulids are coelomates, although unequivocal proof that priapulids are pseudocoelomates would require a fine structural study of the early developmental stages.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00811.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractIn order to elucidate the mechanisms and degree of isolation in the landlocked form of the threespine stickleback,Gasterosteus aculeatus(L.), inhabiting the Shinano and Agano Rivers that flow into the Japan Sea, comparative studies on the morphology, behavior and histology were made of the marine form, the landlocked form and their hybrids reared in the laboratory. The body shape, coloration and behavior of reciprocal hybrids were almost intermediate between the two parent forms. From January to February, the testis of the hybrid between the female marine form and the male landlocked form is occupied exclusively by spermatocytes and some spermatids. However, a small number of large cells, identified as macrophages, are found invading the seminiferous tubules, indicating the occurrence of phagocytosis. On the other hand, ripe functional eggs appear in the ovary in May, i.e. the breeding season. The eggs deposited into the nest do not develop even when the hybrids display the same mating behavior as their parents. Functional sperms are found in the testis of the hybrid between female landlocked and male marine forms at the period of breeding. However, only a single female lived until March. In the ovary of this female, all eggs reaching vitellogenesis (= primary yolk globule stage) are collapsed, while the younger oocytes appear in healthy condition. The hybrid female of this pairing seemed also to be sterile.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00812.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractLight and electron microscopical examination of the paratympanic organ of 8 avian species reveals a sensory epithelium with hair cells and supporting cells, covered by a gelatinous cupula with numerous non‐crystalline deposits. The position of the organ is in agreement with previous suggestions of its function as an air pressure detecto

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00813.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractThe distribution and occurrence of the aminergic structures of the hypothalamus and the hypophysis of the investigated species are very similar, except for the pars distalis. In the tadpoles of the anuran speciesRana temporaria, R. arvalis, R. dalmatina, R. escutenta, Bufo bufoandB. calamita, the pars distalis is aminergically innervated (the Falck‐Hillarp technique), but these nerves disappear at the metamorphic climax. In the larvae of the urodelan speciesTriturus cristatusandT. vulgaris, the pars distalis is devoid of such nerves. Electron microscopical studies ofR. temporaria, B. bufoandT. cristatusconfirm these observations. A discussion of the functional significance of the pars distalis nerves and the phylogenetic role of the difference between anuran and urodelan species is give

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00814.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractConnective tissue components and light microscopical basement membranes ofSaccoglossus horsti(Enteropneusta, Hemichordata) andBranchiostoma lanceolatumhave been studied with Aldehyde Fuchsin, the PAS‐reaction, Alcian Blue (pH 0.2) and fluorescein conjugated (FITC) lectins: concanavalin A (Con A), wheat germ agglutinin (WGA), soy bean agglutinin (SBA), leucoagglutinin (LA),Griffonia (Bandeiraea) simplicifoliaagglutinin (GSA I),Griffonia (Bandeiraea) simplicifoliaisolectin B4(GS I B4). InSaccoglossusandBranchiostoma, both the PAS‐reaction and Alcian blue give a good general survey over the distribution of the principal basement membranes and connective tissue structures. Lectin binding proved less intensive inSaccoglossusthan inBranchiostoma, in which FITC‐Con A, FITC‐GSA and FITC‐WGA react strongly with the dermal (especially in the metapleural folds) and axial connective tissue, as well as the myosepta, the gill arch skeleton and numerous basement membranes. Con A outlines distinctly the major blood vessels in the pharyngeal area. Con A, WGA, GSA and GSI B4are markers for basement

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00815.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractBy means of immunocytochemical methods, a secretin‐like immunoreactivity is demonstrated in the neural complex of the ascidianStyela plicata.Secretinergic neurons are localized in the cortex of the cerebral ganglion and numerous secretin‐like immunoreactive cells are detected in some lobules of the neural gland. The possible functions of secretin‐like substances in the ascidian neural complex are disc

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00816.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

AbstractCoelomocytes ofNephtys coecawere studied by transmission electron microscopy. The majority of the coelomocytes were found to be structurally identical with the muscle cells of the body wall. Animals kept under unfavourable conditions tended to have an increased number of coelomocytes and a decreased thickness of the body wall. The muscular coelomocytes, probably released from the body wall, showed various degrees of decomposition, indicating a process of autophagy.

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1984.tb00817.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY