bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Endoparasites of certain South African snakes, together with some remarks on their structure and effects on their hosts. By the late
Authors: FANTHAM H. B. , PORTER ANNIE 
Published: August 2010

Summary.An account is given of the entozoal fauna found in certain South African snakes, including members of the Boidae, Colubridae, Elapidae and Viperidae.Of the 89 snakes examined, 60 harboured Entozoa, 58 different associations of parasites having been found. These assemblages are detailed. Of these infected snakes, 33 were males and 27 females, of which 12 only were young. The majority of those without Entozoa at the time of examination were also young specimens.A systematic statement of the entozoal assemblages of each infected snake is given, the distribution of the parasites within the hosts being noted. Mature snakes usually contained more species than younger ones and numerically more entozoal individuals were found in full‐grown snakes in poor condition. Flagellates were numerically dominant in most cases.A number of new species of Flagellata, Ciliata and Plasmodia occurring in these hosts are described and their systematic positions discussed. Other parasitic organisms of special interest, but less well known, are also described.The effects of certain Entozoa on their ophidian hosts are described. These include spontaneous intestinal and hepatic amoebiasis, found in members of each of the ophidian families examined, conditions due to ciliate infections, coccidiosis of the intestine and of the gall bladder, pressure effects of cysticerci, intestinal obstruction by helminths, haemorrhagic conditions and hypersecretion of mucus by the lungs due to the presence of helminths, one case of gall stones associated with a trematode infection, and blood conditions, In connection with blood conditions due to Entozoa, the percentage of erythrocytes infectcd with haemogregarines and the alterations of the host cells due to them and to Plasmodium spp. are stated. Mononuclear leucocytosis was found in snakes suffering from liver abscess. The pereentage of eosinophiles associated with single or multiple helminth infestations in some of the snakes is tabulated.A brief comparison is made of the entozoal fauna of these snakes examined in South Africa and of the same species of snakes from West Africa. Distinct similarity is disclosed.The interelations of the hosts and parasites are briefly indicated and their economic significancc stated.
The embryonie development of the mite Tyroglgphus farinae Linnaeus 1758.
Authors: HUGHES T. E. 
Published: August 2010

Summary.

Cleavage, at first total, commences before the accumulation of the yolk, and later becomes superficial.
A blastoderm covering the yolk is formed.
A germinal band is formed by further division of the blastoderm cells along the ventral surface of the embryo.
The band terminates anteriorly in a large cap of cells, posteriorly in a similar but smaller cap of cells.
The anterior cap differentiates into:‐ (a) the central nervous system; (b) the segmental appendages; (c) the anterior plaque of endoderm.
The whole development proceeds singularly directly to the definitive form of the larva.
Coelomic vesicles have not been traced at any stage.
The genital rudiments differentiate from the inner part of the germinal band posterior to the third pair of walking legs and are solid structures.
The posterior polar cap proliferates a mass of cells which indents the yolk at its posterior end and is therefore responsible for the morphological aspects of the lateral caeca.
The posterior mass of cells differentiates dorsally into the mid‐gut, or colon, and ventrally into the upper rectum or post‐colon. The malpighian tubules arise at the upper end of the post‐colon.
The proctodœal invagination sinks into the posterior mass of cells and is the only part of the hind‐gut to be lined with chitin.
The stomodœum arises between the cheliceral rudiments and does not pierce the central nervous system.
Further experimental observations on the spawning behaviour of the Atlantic Salmon (Salmo salar Linn.)
Authors: Jones J. W. , King G. M. 
Published: August 2010

SUMMARY.The 1948 observations confirmed those made in 1947 and produced further data on the behaviour of the adult cock, and the cutting movements of the hen. The fertilized eggs collected from twelve nests gave a percentage fertilization of 97.6. 1,200 ft. of ciné film was exposed.
Some points in the function, development and evolution of the tail in fishes*
Authors: Affleck Robert J. 
Published: August 2010

SUMMARY.

Models show that in fishes the effective action of a tail in a vertical direction depend on:—

the relative size of the epichordal and hypochordal lobes;
the flexibility of the fins;
the direction of the terminal part of the axis;
the relative sizes of the dorsal and ventral lobes of a homocercal tail.

The tails of Carassius auratus, Macropodus opercularis and Betta splendens pass through stages which may be called protocercal and heterocercal before the final homocercal tail is formed.
Because of the precocity of the appearance and functioning of the swimbladder, which causes the specific gravity of the fish to become equal to that of the water in which it lives, no vertical reaction is necessary to keep the larval fish off the bottom when it is swimming. The tail, therefore, is isobatic throughout development.
Whilst passing through the heterocercal stage the flexible epichordal lobe is retained to counteract the upward reaction on the large hypochordal lobe. In ontogeny, therefore, the function of the heterocercal stage of a homocercal tail differs from that of the heterocercal tail found in adult fishes.
In spite of retaining the epichordal lobe during the heterocercal stage, the development of the homocercal tail is primarily recapitulatory.
The possible evolution of tails from a primitive type is discussed in relation to their function and to the specific gravity of the fishes.
It is suggested that the protocercal tail was the primitive type from which were evolved the heterocercal type (associated with pectoral fins) and the hypocercal type (associated with the absence of pectoral fins). The evolution of these tails would enable animals to swim although their specific gravity had increased.
From these two types, five evolutionary lines are traced, each of which terminates in a tail which is exactly, or almost exactly, symmetrical.
The achievement of external symmetry usually signifies that the tail takes no part in raising the posterior part of the animal when it is swimming, or that it is degenerate or specialized.
Some observations on the reproduction of Rattus rattus L
Authors: Watson J. S. 
Published: August 2010

Summary.This paper contains observations on 2612 Rattus rattus from buildings in the port of London, 1519 rats from ships in the docks, both samples obtained during 1941–43, and 1358 rats examined in Cyprus in 1947–48.The sex ratio is considered in relation to the body‐weight of the animals, the method by which they were killed and the locality where they were living.The median body‐weight at which female rats reach maturity in both England and Cyprus in mid‐November to mid‐March is approximately 97 g. The corresponding weight for the rest of the year is 87 g. in England and 78 g. in Cyprus.The pregnancy rate is highest in rats on ships and lowest in rats in Cyprus. Seasonal fluctuations in the breeding intensity is most marked in Cyprus where it is high in April and September and lowest in January. On shore in London the year can be divided into two periods, mid‐November to mid‐March when the breeding rate is declining, and the rest of the year when it is higher; the peak is in September. No obvious seasonal trends in breeding activity are perceptible in rats on ships.The average number of embryos per pregnant female is 7.5 on ships, 6.9 on shore in London and 6.1 in Cyprus. The number of embryos is correlated with the body‐weight of the female, being highest in the heavier animals on both ships and shore in London, but not in Cyprus.At least 25 per cent, of the embryos are lost between implantation and full term in rats on shore in London; the figure is probably smaller in rats on ships and in Cyprus.The proportion of the three colour forms of R. rattus in London was similar on shore and on ships in London; this suggests that the shore population is frequently supplemented by immigrants.
An experiment with populations of fish in Windermere, 1939–48
Authors: Worthington E. B. 
Published: August 2010

Summary. Introduction. Evidence on the biological history of Windermere indicates a change in the associations of fish from one dominated by trout and char to another dominated by perch and pike. Scheme of work. The experiment has involved rapid and drastic reduction in the population of perch since 1940 and pike since 1944, and has been accompanied by research on the bionomics of the various species of fish and on the invertebrate fauna inhabiting Windermere. Perch trapping. The method is described. Trials in 1939–40 were followed by intensive operations with up to 770 traps in 1941 to 1947, The annual migration of perch has been determined in detail. Complete statistics of the fishery have been collected, so that observations are available on more than four million perch. In consequence the varying factors of the environment and of individual behaviour are so masked that conclusions can be drawn from smooth curves plotting the data directly. From 1940 to 1944 inclusive the curves show a simple exponential relation as the population was reduced. Thereafter the fishery reached a condition which approximates to that of a sustained yield, which was one‐eighth to one‐tenth of the original yield in different parts of the lake. The sex ratio has been much disturbed because far more males have been caught than females. Marking experiments and other evidence show little lateral movement of perch along the shore‐line. Pike and eels were taken in perch traps in considerable numbers. Pike netting. The method is described. Trials in 1943–44 were followed by intensive operations in 1944–47, during which period the catches have fallen and presumably the population has been drastically reduced, giving curves similar to those of perch trapping. Char. Regular observations of the fish coming to breed suggests an increase in population following the reduction of perch and pike. The opinions of anglers have given some corroborative evidence of the change of fish populations. Discussion. The probable effects on the rates of reproduction, survival and growth of the five principal species of fish concerned are discussed.
Some oriental spiders of the genus Oxyopes.
Authors: SHERRIFFS W. RAE 
Published: August 2010

Summary.

Eleven oriental species of the genus Oxyopes have been re‐examined and accurate drawings made of the parts essential for their identification.
As a result these eleven species are shown to be separate and distinct from each other, though superficially markedly similar at first sight, e. g. (1) O. papuanus Thor. is apparently not the same as O. striatus Dol. as suggested by Thorell, (2) O. birmanicus Thor. is not “possibly identical with O. similaris Stol.” as stated by Pocock.
A large Scottish fox.
Authors: MATTHEWS L. HARRISON 
Published: August 2010

SUMMARYThe measurements of a large specimen of the hill‐fox from Scotland are recorded, and compared with the measurements previously recorded from similar animals. The conclusion reached by Tetley (1941); that such foxes are indistinguishable from the subspecies Vulpes v. vulpes, the Scandinavian fox, and are distinct from the generally distributed race found in Britain, V. v. crucigera, is supported.
Sub‐surface crypts in the cortex of the mammalian ovary.
Authors: HARRISON R. J. , MATTHEWS L. HARRISON 
Published: August 2010

Summary.Examination of the ovaries from 106 different species of mammals has revealed the presence in a number of them of sub‐surface crypts, lined by germinal epithelium, which penetrate into, or pass through the tunica albuginea. Such crypts are differentiated from intra‐ovarian clefts which simply sub‐divide the ovary and from Pfluger's tubes which have no lumen. The crypts are constantly found in six species of Pinnipeds, frequently in numbers of Marsupialia, Insectivora, many fissiped Carnivora, two species of Procaviidae, Loxòdonta africana, and occasionally in Rodentia and Primates, including the human subject. In the Pinnipedia, and probably in the other species, the maximum development is at the time of oestrus and early pregnancy and the degree of development of the crypts appears to undergo changes corresponding to the degree of follicular activity and oogenesis. Experimental injection of gonadotrophins or oestrogens causes the appearance of crypts in Putorius furo, a species which does not normally show marked crypt formation.The association of crypt formation with oogenesis is discussed and it is suggested that such crypts are possibly a vestige of the primitive pattern of ovarian structure.In the human subject the formation of crypts is associated with the possible subsequent development of fibroadenoma or cystadenoma of the ovary.
The endocranial capacities of the Australopithecinae.
Authors: ASHTON E. H. 
Published: August 2010

Summary.

Modern statistical techniques have been used to compare the endocranial volumes of the Australopithecinae as published by Broom and his associates with those of the chimpanzee, gorilla, and Pithecanthropus.
It is shown that although the endocranial volumes of most of these extinct anthropoids are greater than in the chimpanzee, none differs significantly from the male gorilla, whereas all are significantly smaller than in the hominid genus Pithecanthropus.
Certain published statements about the cranial capacities of these fossils are discussed.
Leaf‐display and the sexual cycle in the Tooth‐billed “Bowerbird” (Scenopœetes dentirostris, Ramsay).
Authors: MARSHALL A. J. 
Published: August 2010

Summary.

The tooth‐billed “bowerbird” (Scenopœetes dentirostris) of North‐eastern Queensland clears a space on the floor of the rain‐forest and on this stage places freshly gathered leaves with their paler and more contrasting under surfaces uppermost. The indentations of the beak appear to be a development directly adapted to the laborious “sawing” by which the bird severs the petioles. The bird has not learnt that (at least with some of the leaves it uses) a sharp downward thrust would disengage the leaf from the tree without great effort.
Stage construction and leaf‐gathering commence at about the period when the testes begin their seasonal maturation. The stages are allowed to fall into disrepair after ovulation and at the time when the testes begin their fatty metamorphosis.
Male birds sit solitarily on a “singing stick” above each stage and sing loudly and continuously for several hours each day during the sexual season. This song, which includes the mimicked calls of other birds, ensures that in the rain‐forest where visibility is restricted every territorial rival or potential mate within a wide area will be aware of the singer's whereabouts.
It is not denied that the birds gain aesthetic pleasure from their leafdisplay and associated activities but it is concluded that these are essentially part of, and are governed by, the sexual cycle. The theory that the display grounds or bowers of this and allied species are primarily “recreational” in function is discounted.
Insufficient data are available to determine more precise functions of the display ground, or the factors that keep the reproductive rhythm “anchored” in time from year to year. These problems are discussed briefly in the text.
The relation between migration‐rate and type of habitat in aquatic inseets, with special reference to certain species of Corixidae.
Authors: BROWN E. S. 
Published: August 2010

SUMMARY.

In a newly filled pond at Haileybury and Imperial Service College, Hertfordshire, the progress of colonization by Corixidae was studied in the spring and early summer of 1949, and again in 1950. The different species appearing were recorded, and compared numerically from sample collections.
The ratio of the numbers migrating into the pond to the numerical abundance of the same species in the surrounding district gave a rough comparison of their migration‐rates, which agreed closely with results obtained by other methods.
Migration‐rates of different species were found to be correlated with the types of habitat which they normally frequent; those normally found in temporary habitats migrate much, while those found in permanent habitats migrate relatively little. Those species of Corixidae whose migration‐rate is restricted by brachypterism are also confined to permanent habitats.
The significance of this correlation between habitat‐type and migration rate is discussed. A high rate of migration is advantageous to species frequenting temporary bodies of water, and a low one to those frequenting permanent habitats. Such a correlation may be more widespread, not only in Corixidae but in other aquatic insects such as beetles.
The factors controlling migration‐rate are (a) anatomical, involving reduction of wings (brachypterism) or of wing muscles (as in the beetle Noterus and the Hemiptera Nepa, Ranatra, Hyocoris), or both; and (b) of some other nature, probably physiological, which affect migratory tendency and behaviour (e. g. Corixidae).
Vestigial metapodials in the Okapi and Giraffe.
Authors: FRASER F. C. 
Published: August 2010

SUMMARY.In the Okapi vestiges of the second and fifth metapodials may be present but they are variable in occurrence and in extent. Metatarsal II is most often evident. This links up with the more specialized Giraffa in which the second metatarsal vestige is the only one which persists.
Notes on external characters of the pouch young of four species of bandicoot
Authors: Lyne A. G. 
Published: August 2010

Summary.The external characters of pouch young of four Australian species of the family Peramelidae have been examined and their principal dimensions are recorded. Three of these bandicoots seem to be in danger of being added to the growing list of extinct marsupials.Particular reference is made to the distribution of the sensory papillae and vibrissae. The numerical constancy of most groups of vibriwae is very marked. In tables 111 and IV, I have summarized the distribution of the vibrissae in seven of the Australian bandicoots.Digits 2, 3 and 4 of the manus of newly‐born young of Perarneles gunnii and Isoodon obesulus bear deciduous claws which are shed soon after the embryo reaches the pouch. The presence of deciduous claws in bandicoots is reported here for the first time. These remarkable claws suggest that the embryo makes its way to the pouch by its own unaided efforts.On the pes, claws are not discernible on newly‐born young.In all but the smallest pouch young the sex may be determined by external examination.
Studies on the crevice fauna of a selected shore in Anglesey
Authors: Glynne‐Williams J. , Hobart J. 
Published: August 2010

Summary.A detailed examination of rock crevices on a selected shore in Anglesey has been made. The tidal levels and percentage exposures of numerous cracks having been established, the contents and certain conditions within the crevice were investigated. These included a mechanical analysis and a qualitative study of the soil particles, estimates of the moisture content, of the humidity of the air trapped in the crevice, and of the organic carbon content of the substrate. A few readings were taken of the air and rock temperatures at the different levels.Qualitative samples of the fauna were taken from crevices a t different tidal levels and from different parts of a single crevice. During the survey forty‐nine species were recorded from this habitat, thirty‐eight of which were plentiful enough for their distribution to be plotted.For the sake of convenience the fauna has been divided into a marine and a terrestrial component. With the exception of Littorina rudis, all animals belonging to the marine component extended down to E.L.W.S., whereas their upper limits were found mainly in one of the three levels of M.L.W.S. M.L.W.N. to E.L.W.N., or M.H.W.N. to E.H.W.N.All the members of the terrestrial component showed a well defined upper and lower limit between tidal marks. Three groups were defined by the extent of their distribution.An examination of the spatial distribution within the crevice also showed differences between the two component parts of the fauna. The marine organisms, with the exception of Eulalia viridis were limited to the outer regions of the crevice, whereas the terrestrial forms were recorded as more common in the inner zone of the crevices at the h e r levels of the beach but more evenly distributed throughout the crevices higher up the shore.Some observations on the feeding habits of the fauna of the crevice have been made in the field and supplemented by further observations made on animals in the laboratory. A diagram showing the possible feeding relationships of the members of the fauna a t different levels is presented.The distribution of this fauna is discussed in relation to the conditions within the crevice; a few remarks on the probable stages in the development of the community are added.
The breeding seasons of mammals in captivity
Authors: Zuckerman S. 
Published: August 2010

Summary.

Representatives of 1049 different mammalian species have lived in the Gardens of the Zoological Society of London during the 110 years intervening between their foundation in 1828 and the end of 1937. 171 belonged to the Order Primates. 316 species, including 28 Primates, have bred.
The records of births have been analysed to show the season of the year which different species breed. A summary of the main results is given in section 5, p. 914 of the main body of the paper.
There is a major physiological difference between a species that never breeds except in a restricted season, and one that breeds evenly throughout the year. The gap between the two is bridged by those animals which, while they breed +nore or less continuously, show a marked seasonal variation in the incidence of births. Theoretically the distinction between the two types of breeding habit can be evaluated statistically, but a more direct way of approaching the problem is the comparison of birth records for successive ten‐year periods. It has been found that the difference between a continuous and a seasonal breeder is often apparent in the records of the first ten years. Even a few birth records may sometimes indicate the breeding habit of a species, and occasionally of the entire genus of which it is a member.
The analysis of the breeding records of a species in successive periods has also occasionally revealed a change in the seasonal incidence of births. It is impossible to determine whether such changes reflect changed climat, ic, conditions or the different habits of different breeding stocks within a species.
An attempt has been made to compare the times when mammals from the southern hemisphere bear their young in London, with the times they breed in their natural habitat (and also to compare the times when mammals from the northern hemisphere breed in zoological collections in the southern hemisphere). There are some thirty‐eight species about which the records are sufficient to indicate breeding habits on the two sides of the equator. Eleven breed continuously in captivity but do not appear to exhibit any marked monthly variation in birth rate on either side of the equator. Two species breed continuously in both the northern and southern hemispheres, with a seasonal peak of births which also appears to be the same on both sides of the equator. In the remaining twenty‐five species most births appear to occur in different months on the two sides of the equator.
During the 1'10 years to which the present records relate, intergeneric crosses have occurred in the family Cercopit'hecidae ofthe order Primates, and in the family B0vida.e of the order Artiodactyh. A large number of interspecific hybrids have occurred in many orders and families.