ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01473.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01474.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1 The well known generic nameGastrochaenahas been applied to the genus formerly known asFistulanaBrug. Consequently the genus formerly known asGastrochaenaSpengler 1783 is now referred to asRocellariaBlainville 1828.2 Specimens ofR. cuneiformisSpengler were obtained from burrows in coral and were studied alive at Raffles Light, Singapore.3 Studies were made of the siphons, the shell, the musculature, the ciliary mechanisms on the structures in the mantle cavity, and also the internal structure and function of the stomach.4 Comparisons were drawn betweenRocellariaand other rock‐boring genera in the family Pholadidae. The most striking feature noted in this comparison was the presence inRocellariaof a shell process at the anterior end of the hinge, on to which the anterior byssus retractor muscle was inserted. This is analogous, if not homologous with the apophysis of the Pholadidae and Teredinidae.5 There are striking differences betweenRocellariaand the Pholadidae in the method of rock‐boring; a stomach appendix, and an accessory visceral ganglion, both present in the Pholadidae, were found to be absent inRocellaria.6 It was concluded that various similarities between Rocellaria and members of the order Adesmacea (Teredinidae and Pholadidae) arose as functional responses to a common mode of life, and are insufficient to indicate that the Gastrochaenidae should be regarded as an early offshoot from the lineage that gave rise t

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01475.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1 An examination of one hundred and fifty‐six species, representing ten families, shows that the otic element does not persist as a separate bone in the adult anuran skull.2 Developmental studies in thirty‐six species from eleven families show that the element is diagnostic of and restricted to the Bufonidae and the Atelopodidae. In every case the bone originates over the dorso‐lateral edge of the crista parotica and subsequently fuses with the squamosal. This supra‐otic position is retained throughout life in the Bufonidae but in the Atelopodidae, the element rotates postero‐laterally until it lies along the outer edge of the auditory capsule.3 In all the Bufonidae and Atelopodidae the depressor mandibulae muscle consists of a single, thick band originating supra‐otically in the former family and latero‐otically in the latter. These conditions are found in no species from any other family. Developmental studies in all bufonid and atelopodid species examined, show that the otic element provides the base from which the depressor muscle originates and it is proposed that the presence of the element and this condition of the muscle are linked characters.4 On the evidence of fossil forms, temporal myology and the compound nature of the fronto‐parietal, the otic element is homologized with a supratemporal.5 From the distribution of the supratemporal bone and its associated condition of the depressor muscle it is concluded that(a) the families Leptodactylidae and Bufonidae should be reinstated,(b) full family status should be accorded to the Dendrobatinae and the Atelopodinae,(c) a close relationship exists between the Bufonidae and the Atelopodidae and the former should be regarded as the ancestral stock,(d) the genusCacophryneshould be regarded as an independent derivative of the arciferalPedostibes stock,(e) Nectophryneshould be returned to the Bufonidae.These conclusions are supported by an examination of the shoulder girdle ofCacophryneand by an inv

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01476.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.A number of cases of infection of the kidneys in birds by trematodes of the genusRenicolaCohn, 1904 is reported and two new species of the genus are described. One of them,Renicola pelecanisp. n., has been found in both the White Pelican (Pelecanus onocrotalus) and the Spot‐billed Pelican (Pelecanus phillipensis). The other,Renicola sloaneisp. n., has been found in a number of species of penguin. It has also been found in a Common Guillemot (Uria aalge) from Sussex, this being the first record of a Renicola from a wild bird in Great Britai

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01477.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1 Previous interpretations of the “stomochord” in the enteropneusts are briefly reviewed.2 Attention is drawn to the possibility that the “stomochord” may be homologous with Seessel's pouch in the

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01478.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.The anatomy of the leechHaemopis sangaisagais described. Whereas all other descriptions of British leeches are based on Whitman's conception of the relation between annulation and segmentation the system here employed is that of Castle and Moore, in which the distribution of the peripheral nerves is used to define the limits of the segments.The alimentary canal differs markedly from that ofHirudo, since the crop has only one pair of lateral diverticula. This may be correlated with the feeding habits, which are macrophagous and not sanguivorous.The nephridia are described in particular detail. It is found that, as inHirudo, the inner end of the nephridial tubules have lost their connection with the ciliated organ, and the latter has no excretory function, but manufactures coelomic corpuscles.

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01479.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.A quantitative assessment has been made of the height of the cells of the follicular epithelium of the thyroid gland of the Minnow,Phoxinus phoxinusL., as an index of the activity of the gland at different seasons of the year. It is possible, despite the considerable degree of variation which occurs, to demonstrate siginificant fluctuations which indicate that the activity is at its maximum during the early months, from about February to May, during which period the maturation of the germ cells is known to be completed. The maintenance of minnows at constant temperatures for fifty‐seven days gives no evidence of an inverse relationship between temperature and cell‐height such as is known to exist in certain homoiotherms, but actually suggests a direct one. It seems unlikely, from the available data, that, the thyroid fluctuations can be a response to temperature changes in the environment, and it is concluded that there is an indication in the minnow, as elsewhere in the vertebrates, of some correlation of the activity of the thyroid gland with the phases of the reproductive cycle, the causal basis of which is, however, obsc

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01480.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1 Linear measurements, tusk weights, sex, and locality of origin are given for a series of elephants shot in Uganda.2 Photographic records of the molar dentition have been used to assess the relative age of specimens and to put selected animals in order of age at death. Comparison with captive elephants of known age shows that wild female African elephants usually begin to breed at eight to twelve years, and examination of very old animals showed that they may be capable of breeding until extreme old age.3 A diagram has been constructed to relate the body size and tusk size of individual animals to their position in a series arranged in order of age (according to the condition of the molar teeth), the sex being indicated in each case. The diagram includes fifty‐seven animals for which all the relevant data are available and it shows that:(i) Growth is noticeably uniform within the sample.(ii) Males and females grow more slowly after puberty but continue to grow for a considerable time. Growth probably continues until late in life or until death.(iii) Males are generally bigger than females of the same age.(iv) The tusks of females usually cease to grow after puberty.(v) The tusks of males sometimes cease to grow after puberty, but more usually continue to do so. Their growth may continue at the same high rate as before puberty, or it may be slowed to a greater or lesser degree. Large tusks are evidently the product of rapid growth rather than longevity, and exceptionally large tusks are probably attributable to the survival to old age of an animal whose tusks have continued to grow at a higher rate

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01481.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY

摘要:

Summary.1 Dissection of Hake,Merluccis merluccius, has shown that the encysted metacercariae ofBucephalopsisare distributed on the brain and cranial nerves in the head region, and on the spinal nerves in the tail region.2 In the head region the nerves on which the cysts occur are those supplying the lateral line system.3 It is shown that in the tail region there is a path, via the lateral line canal, to the spinal nerves.4 It is concluded that the Hake is infected by the cercariae entering the lateral line

ISSN:0370-2774    

DOI:10.1111/j.1096-3642.1954.tb01482.x

出版商:Blackwell Publishing Ltd    

年代:1954

数据来源: WILEY