摘要:

Holothuria poliibrown bodies are associated with the defence mechanisms of the host. Naturally and experimentally induced brown bodies are histologically constituted by nodules in a granular extracellular matrix containing distinct spherule cell types. Nodules of natural brown bodies consist in flattened amoebocytes surrounding large antigens, whereas nodules from experimentally induced brown bodies originate from the aggregation of phagocyting amoebocytes. An extracellular granular matrix characterizes both types of brown bodies. It probably originates from degranulation of spherule cells.

ISSN:0373-4137    

DOI:10.1080/11250008909355651

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The ultrastructure of the excretory‐secretory system ofToxocara canisinfective larvae is described. The system is composed of a single uninucleate cell forming two elongate columns that extend throughout the length of the worm up to the anterior portion of the intestine. The cytoplasm shows an abundant endoplasmic reticulum and an extensive Golgi complex from which many vesicles of variable density originate. The material of the vesicles is discharged into the lumen of an intracellular duct crossing the two columns of the gland cell. These ducts appear as sinuous canals surrounded by a series of small, interconnected cavities. The excretory ducts join by means of transversal canals which, in turn, flow into a common duct opening outside through an excretory pore.

ISSN:0373-4137    

DOI:10.1080/11250008909355652

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

In Ephemeroptera, in spite of the absence of accessory glands in the female genitalia, the eggs frequently show adhesive coats. Ul trastructural observations of the female reproductive apparatus ofHabrophlebia eldaedemonstrated that the elaboration of chorionic adhesive layers takes place in ovarioles and oviducts. In ovarioles, follicle cells synthesize viscous material that is released on the chorionic surface, and that coalesces to form: a) electron‐dense masses closely packed on both sides of the ridges that characterize the fully formed chorion in this species; and b) a thin granular layer that covers the egg surface before ovulation. During passage through the oviducts, the chorion is enriched by products secreted by the cells delimiting the oviductal lumen.

ISSN:0373-4137    

DOI:10.1080/11250008909355653

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The seminiferous epithelium cycle of the common shrewSorex araneusL. is described. On the basis of acrosome formation and spermatid differentiation, the male germ cell cytodifferentiative process was divided into ten stages characterized by typical cell associations. The common shrew has an interesting and variable karyotype, and detailed knowledge of the seminiferous epithelium cycle is required to compare the spermatogenic process in karyotypic homo‐ and heterozygotes.

ISSN:0373-4137    

DOI:10.1080/11250008909355654

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Morphological observations by means of scanning electron mi croscopy and electrophysiological tests consisting of electroanten nogram recordings (EAGs) were performed on the third antennal segment (flagellum) of female and maleCeratitis capitataWied. The number and the distribution of the four types of chemosensilla present on the flagellar surface (basiconic, clavate, trichoid, and grooved) were not related to sex, and sex did not influence the responsiveness of the flagellar chemosensilla to some volatiles usually occurring in the habitat ofCeratitis.Ethanol, butanol, amyl alcohol, 1‐hexanol, and hexanal proved to be the most effective stimulants, while 1‐nonanol, 1‐decanol, octyl aldehyde, and nonyl aldehyde did not exert relevant stimulating effects. Concerning the specific responsiveness of the chemosensillar types, basiconic and clavate sensilla were of major importance in EAG responses to short chain aliphatic alcohols such as ethanol, butanol, and amyl alcohol.

ISSN:0373-4137    

DOI:10.1080/11250008909355655

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

An induced agglutinin was observed inPlanorbarius corneusafter challenge with livingStaphylococcus aureus.Purified agglutinin has a M W of about 330–350 kilodaltons and shows an agglutinin titer of 128. This agglutinin does not present antibacterial activity.

ISSN:0373-4137    

DOI:10.1080/11250008909355656

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The predatory behaviour of captive wild kestrels was investiga ted to ascertain whether prolonged captivity, with no predation opportunities, could affect prey capture. Thirty kestrels were ob served. After a 48‐hour fast they were offered a live laboratory mouse. The behaviour before and after prey appearance, and la tency to predation were recorded. There was no difference in cap ture efficiency correlated with kestrel age, but adults performed preening significantly more often than young birds. Moreover, a clear inverse correlation was found between the latency of preening and of predation. Therefore, prolonged captivity associated with inactivity does not seem to exert a negative influence on predation in this species.

ISSN:0373-4137    

DOI:10.1080/11250008909355657

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

A survey tour was made to examine the insect fauna ofUrtica dioicain central and southern Europe and compare it with that in Britain. Forty‐five sites were sampled mainly in Italy and southern Germany. The range of habitats occupied byU. dioicais described. Over 100 insect species in 6 orders were identified of which about 48 phytophagous species and several predatory species are consi dered to be closely or commonly associated with the host plant. Some regional variations were found but the fauna is basically quite similar throughout the area covered.

ISSN:0373-4137    

DOI:10.1080/11250008909355658

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The relationships between the 13 most common species of Por tuguese earthworms and 20 soil characteristics have been investi gated by analysis of ecological profiles, correspondence analysis and canonical correlation. Two groups emerged: one comprising basi cally the epigeic speciesAllolobophora oliveirae, Dendrobaena madeiren‐sis, Dendrobaena octaedraandEisenia eiseni,which tend to prefer organic acid soils with little calcium or magnesium and large quan tities of aluminium in the exchange complex, and the other made up of the endogeic speciesAllolobophora caliginosa, Allolobophora mol‐leri, Allolobophora roseaandAllolobophora chlorotica,which exhibit the opposite tendencies.

ISSN:0373-4137    

DOI:10.1080/11250008909355659

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The Papilionoidea of the Philippines and Palawan were studied with different statistical methods to show distribution and faunistic similarities. The results can be summarized as follows: a) Palawan is significantly different from the Philippines, while the similarities are virtually undistinguishable from Borneo and Malaysia; b) the high percentage of taxa endemic to the Philippines and the low faunistic similarity with the surrounding areas of Malaysia, Borneo and Taiwan demonstrate that the butterflies of the Philippines are well characterized; c) the total number of species on each island is significantly correlated with the island area and less influenced by the distance from the source‐pools; d) the total number of endemic taxa on each island is highly correlated with the island area; e) there are different behaviours in the relation species‐area in each family.

ISSN:0373-4137    

DOI:10.1080/11250008909355660

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor