摘要:

The body surface ofMicrostomum lineare, Bothriomolus balticusandArchilopsis unipunctatawas examined in scanning electron microscope. The threedimensional appearance of adhesive duo‐gland organs, receptor cilia, globular bodies and pistil‐like projections is described. The adhesive duo‐gland papillae ofBothriomolusandArchilopsisappear as bouquetlike structures on either side of the tail as well as on the cilia covered body. InMicrostomumthe papillae occur as single projections among the ciliary body für. Supplementary TEM investigation revealed crystalline bodies in the cytoplasm of viscid gland

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00583.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Four species of digenetic trematodes of marine fishes from Belize are studied for allometric growth:Multitestis rotundusSparks, 1954 (Lepocreadiidae),Stenopera equilataManter, 1933 (Opecoelidae),Leurodera decoraLinton, 1910 (Hemiuridae),Prosorhynchus pacificusManter, 1940 (Bucephalidae). These are compared with six other species for which allometric growth is known. Positive growth is exhibited in all species only by the hindbody, whereas the forebody, suckers, and pharynx are negative in all. The body width, post‐testicular body, and gonads are positive in some species and negative in others. At times the body proportion or organ is growing at about the same rate as the body lengt

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00584.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

The reproductive system of the type specimens ofDistoma macrostomumandD. ringensRudolphi, 1819, has been reinvestigated. The shape and position of the cirrus, cirrus pouch, metraterm, “vesicula seminalis”, gonads, vitellaria and uterus arrangements are given. This shows that the arrangement of the reproductive system inD. macrostomum(syn.D. ringens) differs from that of the members of the generaLeucochloridiumCarus, 1835 (sensu Kagan 1952) andNeoleucochloridiumKagan, 1951. It confirms as correct to placeD. macrostomumas a separate genus,UrogonimusMonticelli, 1

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00585.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

The ultrastructure of the head end and surface structure of the cuticle ofSyphacia petrusewiczi, S. nigeriana, S. fredericiandS. stromawas studied. These species may be easily separated on the basis of the differences in their morphology:S. fredericipossesses longitudinal septa on the body surface, a row of denticles on each of the three main teeth, and cervical alae;S. nigerianahas longitudinal septa and denticles but lack cervical alae; S.petrusewiczihas longitudinal septa and cervical alae but lacks denticles;S. stromalacks these three characters.

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00586.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

The dermal bones ofBirgeriaandScanilepiscontain numerous odontodes of consecutive generations, each consisting of dentine and a single ganoin layer; superimposition of series of ganoin layers, generally encountered in the scales of the palaeonisciforms. does not occur in any of these bones. InBirgeria, some odontodes near to the dentition resemble jaw‐teeth proper in possessing an apical portion of acrodin; furthermore, nothing indicates the existence here of nerve‐sac groups like those of sturgeons. The histology of the dermal skeleton inScanilepisdoes not support the assumption that this form is more closely related toPolypterusthan other palaeonisciforms. Remarks are given on the structure of acrodin and ganoin as revealed by SEM st

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00587.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Teeth from specified members of the two suborders of Late Cretaceous Multituberculata and two Late Cretaceous therians were studied. The enamel was prismatic on all teeth. In the therian representatives and the representatives of the suborder Ptilodontoidea of the Multituberculata, the prism diameters and densities per unit area were similar to those of recent mammals. In the representatives of the suborder Taeniolabidoidea the prisms were very large and their density per unit area was 5 to 8 times lower than in recent mammals. It is suggested that gigantoprismatic enamel is a characteristic of Taeniolabidoidea and could be used as a taxonomic criterion in multituberculate systematics.

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00588.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

A detailed description is given of the lower jaw and cervical vertebrae of an almost complete skeleton of a baleen whale,Mesocetus argillariussp.n., from the Gram Formation of Jutland, Denmark. After comparison with other baleen whales it is concluded that the Miocene species ofMesocetusare closely related to recent balaenopterids, although not their direct ancestors. The relationship to recent balaenids is more remote. The voluminous mandibular canal found in variousMesocetusspecies, inPelocetus mirabilisand in some Arahaeoceti e.g.Zygorhiza kochiandDorudon osiris, may be one of the prerequisites for the development during whale phylogeny of the echolocation system found in a highly refined form in modern Odontoceti. Asymmetry in the cranial skeleton characteristic of modern odontocetes seems to be closely linked with the echolocation system and when detected in fossil forms, it may indicate that this system was already established there. Accordingly, it would appear from forms such asDiochotichus vanbenedeniandProsqualodon australisthat some sort of echolocation was in existence as early as in the Lower Miocene.

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00589.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

A new interpretation of the anatomy and systematic position ofPeraclistus oofagus, an ectocommensal on the queen crab,Chionoecetis opilio, is presented.P. oofagusis redescribed and it is claimed that the original interpretation was erroneous. The genusPeraclistusis redefined both on the basis of this study and on examination of the type material, of the other members of this genus.

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00590.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Previous work on species ofProleptusDujardin, 1845 and related genera is briefly reviewed.Proleptus mackenzieisp.n. is described and figured.P. mackenzieiis close toP. obtusus, P. acutusandP. malayibut differs from them in the host, position of the vulva which is 2/5/ of the body length from the anus and in the detailed arrangements of the papillae on the male tail.

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00591.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

A comparative structural and ultrastructural investigation is made of genital organs of selected, genera of Thaumastodermatidae and their constructions are defined. Two new subfamilies are designated within the family based on reproductive features and other characteristics. The occurrence of bounding epithelia about the gonads, ova and central body region is noted. Paramyosin type muscles are noted forPlatydasys.General and specific features of spermatogenesis, oogenesis and fertilization are defined and discussed. The evolution of accessory reproductive organs in Macrodasyida is discussed.

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1978.tb00592.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY