bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Relation of Instar Length to the External and Internal Environment in Tegenaria atrica (Arachnida).
Authors: Browning H. C. 
Published: August 2010

Summary.1. The influence of temperature, humidity, food, light, parentage, age, and sex on instar length and its variability in Tegenaria atrica was investigated.2. Only one factor of the external environment was varied at a time. The factors were:–20o C, 25‐5o C, and 30o C.; 8‐25, 16‐36, and 23‐13 mm. saturation deficiency; two food levels in excess of the needs for an instar and one at the minimum amount; light and darkness.3. A threshold amount of food was required for completion of an instar, and this quantity was greater when the rate of feeding was lower. It also increased as temperature fell and saturation deficiency rose, but illumination had no effect.4. Instar length decreased as temperature rose, as saturation deficiency fell, and when the animals were illuminated.5. Different amounts of food, provided that they were more than the minimum needed for instar completion, had no effect on its length. An instar which had only the minimum amount was slightly lengthened and the following one, with excess food, was considerably shortened.6. Variance of instar length increased at the lowest humidity, with minimum feeding, and with age, decreased with rise of temperature, and was unaffected by illumination.7. In regard to internal environment, the offspring of various parents fell into three groups, each with its own inherent mean instar length; instar length always increased with age; and the sexes of the animals were indistinguishable.8. The above results and their relation to work on insects are discussed, and it appears that the moult cycle of T. atrica is controlled in a similar manner to that of Rhodnivs and Cimex. However, this and other spiders show a striking variability in individual instar lengths.
Further Experimental Studies of the Selective Action of Predators.
Authors: Popham E. J. 
Published: August 2010

Summary.(1) The Intensity of Selection is influenced by the population density of the types of prey and predators.(2) When the types of prey are not in equal proportions, those insects present in the largest numbers are destroyed relatively faster than the others.(3) While the Selective Action of Predators can be reduced, or even eliminated, it has not been found to act in any way that would result in the preservation of a harmful or neutral character.(4) Selection on mottled backgrounds may be less intense than on an even background of the same colour., where the mottling is approximately the same size as the insects.(5) Insects with one or both hind legs amputated are destroyed faster than normal insects.(6) Both sexes of Sigara distincta (Hemiptera, Corixidse) are destroyed equally.(7) Scardinius erythropkthalmus (Rudd) are able to distinguish between certain species of Sigara.(8) Nymphs of Hydrarachna geographica (Water Mites) tend to parasitize most those Corixids which do not harmonize with their environment.(9) Males of Sigara distincta tend to choose as a mate a female either the same colour as themselves or slightly lighter.
Reproduction in the Water‐Vole, Arvicola amphibius Linn.
Authors: Perry J. S. 
Published: August 2010

Summary.1. Reproduction in the water‐vole, Arvicola amphibius, is described from field material comprising 128 males and 95 females.2. The reproductive organs resemble those of the bank‐vole.3. The breeding season extends from the end of March to the latter half of September, but fecund males were caught in February.4. Animals born early in the year breed in the same season. The average number of corpora lutea of pregnancy was 6‐4 and of embryos in utero 5–7.5. Males are non‐fecund in winter, when the testes are very small; the testes of non‐fecund adults can be distinguished from those of immature animals by the condition of the tunica albuginea.6. The female has a poly‐cestrous cycle, and both non‐parous animals and parous animals at the beginning of their second year may undergo infertile cycles. (Estrus is accompanied by distension of the uterus with fluid as in the rat and mouse.7. There is a post‐partum oestrus, and several animals were found to be pregnant and lactating. Animals which fail to become pregnant at the postpartum oestrus enter upon a lactation anoestrus. This may be followed by another oestrus, but late in the season the animal passes from lactation anoestrus to winter anoestrus without ovulating again.8. The ovarian follicles reach about 700/J. in diameter at oestrus, but large follicles are also found at all stages of pregnancy. The corpora lutea reach their maximum size, about 1–7 mm. in diameter, fairly late in pregnancy.9. Cyclical changes in the Fallopian tubes and uterus are described.10. The mammary glands afford good evidence of the condition of the animal and make it possible to distinguish between the first pregnancy of the season and a subsequent pregnancy.The material described above was obtained in 1932‐35 as part of a general programme of work on the reproductive processes in British mammals, and was made available to me by Dr. A. S. Parkes, who suggested this work.
STUDIES ON THE FOOD OF COLLEMBOLA IN A DOUGLAS FIR PLANTATION
Authors: POOLE T. B. 
Published: August 2010

SUMMARYAn examination of the visible gut contents of Collembola showed that the larger species feed mainly on soil Fungi, whereas the smaller forms appear to feed directly on the humus. There seemed to be no consistent differences in the feeding habits of species of similar size but there was some evidence of seasonal variations in the arnount of Douglas fir litter consumed by Collembola.Experiments with Tomocerus longicornis indicated that viable soil Fungi pass through the collembolan gut; it is therefore probable that they play an important role in the dispersal of soil Fungi.
THE RESPONSE TO LIGHT IN ICHTHYOPHIS (AMPHIBIA‐APODA) FROM CEYLON
Authors: ROSS D. M. 
Published: August 2010

SUMMARY

Specimens of the virtually blind apodan, Ichthyophis glutinosus, have been exposed to general and local illumination, their sensitivity to light confirmed, and the character and timing of the resulting movements analysed.
To general illumination the animal usually gives a general stirring and locomotory resopnse after a considerable and variable delay.
In some animals this general response is preceded by a shock reflex, the twitch response, the reaction times of which are reasonably consistent and show the intensity/duration relationships discovered by Hecht in automatic light reflexes in Ciona and other animals.
The twitch resopnse gives an estimate of the minimal reaction time and shows that the long delay and variability in the timing of the general locomotory movements are due to central processes which determine the response to light in accordance with the general condition and activity of the animal at the time.
Ichthyophis is sensitive to light falling anywhere on the head, and on the tail from above. The rest of the body is only slightly sensitive.
Local illunination on the head or tail gives rise usually to the general locomotory response, but with caudal illumination a local reflex with a very short reaction time precedes the general response. Judged both from reaction times and from numbers of responses obtained, the tail seems to be more sensitive to light than the head.
Operations showed that for a general response to develop from caudal illumination, the spinal cord must be intact, but the local tail reflex is not affected by spinal section.
The response of the head to light was not affected by severing the optic nerves.
The time relations, sensitivity, general character and spatial distribution of the dermal light sense of Ichthyophis are discussed in relation to the mode of life of the animal and it is concluded that in all respects, its properties coincide very remarkably with the animal's needs.
THE SKIN AND NUCHAL EMINENCE OF THE WHITE RHINOCEROS
Authors: CAVE A. J. E. , ALLBROOK D. B. 
Published: August 2010

SUMMARY

The skin histology of an immature White Rhinoceros is described. The thin epidermis has the customary layers, the deepest layer being pigmented. It sends into the dermis hair follicles (containing hair shafts), small sebaceous glands and large apocrine sweat glands characterised by enormous ectodermally‐developed myoepithelial cells.
The exceedingly thick and well vascularised dermis is exclusively collagenous in composition.
The hump or nuchal eminence is merely a local augmentation of the dermis (nuchal node).
REVISION OF THE CLARIID CATFISHES OF NYASALAND, WITH A DESCRIPTION OF A NEW GENUS AND SEVEN NEW SPECIES
Authors: JACKSON P. B. N. 
Published: August 2010

SUMMARYA study was undertaken of catfishes of the family Clariidae in Nyasaland, excluding that small part of the Shire River system which lies below the Murchison cataracts. Of fourteen species found, four, belonging to the genus Clarias, are not endemic and are found mainly in rivers, streams and swamps, inhabiting Lake Nyasa sparsely and only where similar conditions are found. The lake has been colonised mainly by the remaining ten species, which are all endemic to it, specialised for lacustrine conditions and sufficiently distinctive to warrant a new genus being proposed: genus Bathyclarias nov. The ten species of the genus form a species‐flock, having a variety of habitats. Seven are new and are described and figured: Bathyclarias loweae, B. ilesi, B. rotundifrons, B. euryodon, B. filicibarbis, B. worthingtoni and B. gigas, spp. n. Notes on distribution and ecology are given in all cases, and a key is given for all members of the family in Nyasaland.
THE STRUCTURE AND FUNCTION OF THE ALIMENTARY CANAL INLINGULA UNGUIS(L.) (BRACHIOPODA)*
Authors: CHUANG S. H. 
Published: August 2010

SUMMARYThe anyonomy and histology of the alimentary carnal in Lingula unguisThe coutrse and function of the ciliated epithelial groove are described.The ciliary currents within the gut are traced. These merely agitate the gut contents.The pH of the contents of the stomach was determined.Experimentally fed particles passed through the pharynx, oesophagus and the anterior loop of the intestine rapidly, but were retained longer in the digestive diverticula, the stomach and the straight part of the intestine.After feeding the digestive diverticula relax and contract rhythmically, thus sucking the fluid and suspended particles from the stomach and then squirting them back into the stomach again. The contents of the intestine are propelled by peristaltic, antiperistaltic, constricting, segmenting and pendular moverments.Phagocytosis occurs in the digestive diverticula, stomach and intestine; but ingestion occurs most actively in the acini of the diverticula.A weak protease and a weak lipase were fomtd only in extracts of the digestive diverticula. An amylase was found in the stomach contents and in extracts of all regions of the gut from the stomach to the intestine. A sucrase, inulase, maltase, lactase and raffinase were found in extracts of both the diverticula and the intestine.In Lingula, unguis digestion is mainly, if not exclusively, intracelluur. There is evideiice of extracellular digestion of starch and glycogen in the lumen of both the stomach and the digestivc diverticula.Comparisons are made with other brachiopods and with Phoronis, ectoprocts, endoprocts, lamellibranchs and Amphioxus.
A REVISION OF THE BRITISH SYMPHYLA
Authors: EDWARDS C. A. 
Published: August 2010

SUMMARYThe collection, occurrence and geographical distribution of the British Symphyla is discussed. Methods of making temporary and permanent mounts suitable for taxonomic study are outlined.Eight species of Scutigerellidae, belonging to three genera are described, one species being new to science and four new to the British Isles. Six species of Scolopendrellidac belonging to three genera, one species being new to science and one new to the British Isles are described.Symphyla vary considerably in size and chaetotaxy and because of this as many specimens as possible from a wide range of localities have been studied; in all, specimens from 317 localities. This has enabled the range of variation to be expected in each species to be outlined.
THE NUMBERS OF EXHIBITS, BIRTHS AND DEATHS IN THE MENAGERIE AT REGENT'S PARK: 1835–1957, AND IN WHIPSNADE PARK: 1931–1957
Authors: ASHTON E. H. , VEVERS H. G. 
Published: August 2010

SUMMARY

Comparisons have been made, between the present‐day conditions and those existing during earlier phases of the Society's history in respect to:

the numbers of vertebrates (excluding fish) exhibited in the menagerie.
the proportion of the total vertebrate exhibits accounted for by (i) mammals (ii) birds (iii) reptiles and amphibians.
the birth rate.
the survival rate of vertebrates born in the menagerie.
the mortality rate.

Apart from the period during the Second World War when the numbers of vertebrates dropped sharply, the collections have, since the mid‐1930's, fluctuated around a level of some 5000 exhibits. The numbers of species and subspecies have, during the past seven years, varied slightly around an average of approximately 1200.
Mammals now account for some 30 per cent of the total exhibits, birds for 60 per cent while reptiles and amphibians comprise 10 per cent. Approximately 90 per cent of the mammals and birds exhibited are from wild species.
The birth rate in the collections as a whole now stands at 14 per 100 exhibits. The corresponding value for wild species is 11.8. These figures are among the highest attained during the periods for which records are available.
ore than 90 per cent of the animals born in the menagerie during 1957 survived to the end of the year. The average survival rate for the past three years is higher than at any time since the opening of Whipsnade Park in 1931.
The mortality rate for the entire vertebrate collections stood, during 1957, at 21. This figure is less than at any time either before or after the Second World War.
A REPORT ON THE PARASITIC COPEPODA AND BRANCHIURA OF THE FISHES OF LAKE BANGWEULU (NORTHERN RHODESIA)
Authors: FRYER GEOFFREY 
Published: August 2010

SUMMARYAn account is given of the parasitic Copepoda and Branchiura of the fishes of Lake Bangweulu.At least seven species of parasitic Copepoda and seven species of Branchiura are now known to occur in the lake, one copepod and three branchiurans being described as new in the present paper.The systematic status of the specimens of Chonopeltis previously described from the lower part of the Congo system under the name of C. inermis var schoutedeni is discussed, and it is shown that two distinct species, neither of them C. inermis, were obscured by this name.Notes on the structure and biology of individual species are given.The distribution of the species recorded supports and supplements the idea derived from a study of fish distribution that migration has, in the past, been possible between the Congo and Zambezi systems, and also between the Congo and Nile systems, yet at the same time has emphasised the isolation of Lake Nyasa and the endemic nature of some of the species of Lernaea recorded from that lake.
VERNAL COITION OF THE SEAL PHOCA VITULINA IN SHETLAND
Authors: VENABLES U. M. , VENABLES L. S. V. 
Published: August 2010

SUMMARY

A colony of Phoca vitulina was under regular observation from 23rd May to 10th June 1958. Outbursts of sexual rolling were common between subadult pairs. No yearlings and no pregnant females took part, and fully grown bulls did so rarely.
Both sexes rolled enthusiastically. Changes of partner were rare. Many males appeared eager for coition but the females, by arching back their heads and necks, usually prevented them from getting far enough forward for insertion. Successful coition was witnessed on at least one, possibly six, occasion(s).
Probably rolling females were maiden cows, approaching oestrus. Ovulation can occur in May and may well be stimulated by this prolonged riding behaviour.
The main mating season (September‐October in Shetland) follows lactation and moult. In our three years' experience of this colony all pups were born during the three weeks commencing 14th June. If successful fertilization occurs in May, the implantation of the blastocyst is probably delayed until the normal season.
A recent decline in the size of this seal colony may be due to the increase in price offered for pups' pelts with a consequent increase in hunting.
THE NASAL FOSSA OF A FOETAL GORILLA
Authors: CAVE A. J. E. 
Published: August 2010

SUMMARY

The anatomy of the nasal fossa is described for a gorilla foetus approaching term.
Of the paranasal sinuses, a maxillary and a posterior ethmoidal sinus alone are present and are well established.
Sphenoidal, frontal and anterior ethmoidal sinuses have not as yet begun to develop.
Beneath a prominent bulla ethmoidalis and above a strongly developed plica semilunaris, an ostium maxillare opens directly into the middle meatus.
In addition to a naso‐turbinal, a maxillo‐turbinal and ethmoturbinals I and II, a rudimentary ethmoturbinal III is present.
THE STATUS AND AFFINITIES OF THE ANTHOMEDUSAN PARAGOTOEA BATHYBIA KRAMP, 1942
Authors: RALPH PATRICIA M. 
Published: August 2010

SUMMARYThree specimens of a rare anthomedusa collected by the R.V. “Sarsia” west of the English Channel, are described and compared with Paragotoea bathybia Kramp, 1942 and have been identified with it.With age, the number of tentacles increases from one to four and a quadrate stomach with four stomach pouches is developed as the medusa matures.A quadrate stomach is regarded as significant in determining the affinities of Paragotoea and a new anthomedusan family Paragotoeidae is created for it.Pending the discovery of more specimens of the Japanese form, Gotoea Uchida 1927, is recognized as distinct from Paragotoea and retained in the family Tubulariidae.
STUDIES ON THE FUNCTIONAL MORPHOLOGY OF GERRIS NAJAS DEGEER (HEM. HET. GERRIDAE)
Authors: BRINKHURST R. O. 
Published: August 2010

SUMMARYVarious aspects of the morphology of a. najas are described from a functional viewpoint, and experimental evidence is used to support some of the conclusions reached. Special attention is focused on the structure of the hypopharynx and the associated structures, and the function of the mandibular muscles is reassessed. The thorax is considered as a functional unit in relation to locomotion, and experiments on the mechanism of rowing, with its significance in regard to alary polymorphism are described. The reactions of Gerris species to surface tension are investigated. Preliminary observations are made on the function of the metasternal gland in this genus. The structure and function of the reproduotive system in both aexes are disoussed, with some observations on the eggs, oviposition and development. A new interpretation of the spermatheoa is presented. Many aspects of the morphology are shown to be adaptations to life on the surfaae film of water.
THE FOOD OF A SAMPLE OF CROCODILES (CROCODILUS NILOTICUS L.) FROM LAKE VICTORIA
Authors: CORBET PHILIP S. 
Published: August 2010

SUMMARY

The stomach‐contents of sixty‐seven crocodiles from Napoleon Gulf, Lake Victoria, and two from elsewhere in Uganda have been examined. The lengths of all crocodiles were recorded.
In recording the results, consideration has been given to the size and abundance of food items, as well as to the frequency of their occurrence. A detailed list of stomach‐contents is given, and also brief notes on some of the food organisms.
These data confirm previous observations on the food of crocodiles in Uganda in so far as they demonstrate a change in diet with size. In the present series, insects provided the most important food of crocodiles less than 1 metre long, but larger individuals fed to a progressively greater extent on fishes and other vertebrates.
STUDIES OF A NUTRITIONAL DISEASE (OSTEODYSTROPHIA FIBROSA) OF YOUNG LIONS ASSOCIATED WITH CHANGES OF THE SKELETON AND SYMPTOMS OF MUSCULAR WEAKNESS
Authors: T‐W‐FIENNES R. N. , GRAHAM‐JONES O. 
Published: August 2010

SUMMARY

Studies have been made of a disease of young lions in captivity which has been a source of difficulty in many zoos and other places.
These studies have embraced the symptoms and course of the disease, the clinical and pathological symptoms, the morbid anatomy and the biochemistry.
This disease had hitherto, owing to the outward signs, been ascribed to a variety of causes including myopathy and various vitamin and other dietary deficiencies.
The studies have shown that a number of the bodily systems suffer derangement or damage during the course of the disease, and a number of possible causes required to be eliminated. Thus apparent changes occur in the skeletal system, the nervous system, the alimentary system, and the endocrine system. In addition there was the possibility that the disease might be associated with helminthiasis or with the effects of post‐viral infection.
It has been demonstrated that the primary lesion is that of the skeleton and that this is an osteodystrophia fibrosa resembling the well‐known condition described by Theiler and others.
The disease appears to be associated with an unnaturally low Ca/P ratio in the diet normally fed to captive lions which consists mainly of red meat. It has not been widely recognised that the Ca/P ratio of red meat is about 1: 20 and that lions consume bones only sparingly and thus do not tend to correct this wide ratio.
Once established, skeletal deformities tend to subsist and complete cure in the sense of a return to normal cannot be effected by correction of the dietary ratio. Great improvement has, however, been effected in the case of one lioness who was given calcium supplements and improved to such an extent that she was able to go back on exhibition in the Zoological Gardens. Two other young lions, sent from Whipsnade Zoo for treatment, were subsequently cured by similar means.
OBSERVATIONS ON THE ORIENTATION AND FEEDING OF THE COPEPOD SABELLIPHILUS ELONGATUS M. SARS ON ITS FAN‐WORM HOST
Authors: GOTTO R. V. 
Published: August 2010

A detailed account is given of the alignment, attitude and behaviour of the cyclopoid copepod Sabelliphilus elongatus on the branchial filaments of the polychaet Sabella pavonina.It is thought that the direction of alignment is governed by the withdrawal reaction of the host, both orientation and posture being designed to avoid dislodgment from the fan during this movement.The copepod appears to rely for correct orientation on its sensitivity to the ciliary action of a small rejection tract on the filament's abfrontal surface.Evidence is presented for regarding S. elongatus as an ectoparasite which extracts oil or fat by slight erosion of the pigmented epithelium, and which may also utilise mucus. Cells producing the latter substance are possibly stimulated through contact with the parasite's antennal claws.
STUDIES ON SOME PARASITIC CRUSTACEANS ON AFRICAN FRESHWATER FISHES, WITH DESCRIPTIONS OF A NEW COPEPOD OF THE GENUS ERGASILUS AND A NEW BRANCHIURAN OF THE GENUS CHONOPELTIS
Authors: FRYER GEOFFREY 
Published: August 2010

SUMMARYTwo new parasitic crustaceans of African freshwater fishes are described. These are the copepod Ergasilus Zutue, from L. Rudolf, and the branchiuran. Chonopeltis flaccijrons from various parts of the Congo system.A description of the true male of Argulus ambloplites is given, and in the light of its structure it is suggested that A. jollymani is best regarded as a sub‐species of A. ambloplites.The male of Argulus dartvellei is described for the first time.Notes of the specimens of Chonopeltis recorded from the Ue 16 and Okavango Rivers are given and it is shown that neither can be satisfactorily identified at present.Keys to the species of Chonopeltis are given.Some recently established diat ribution records of parasitic crustaceans of African freshwater fishes are listed.