bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reproduction in the rat‐tailed bat Rhinopoma kinneari
Authors: Kumar T. C. Anand 
Published: August 2009

A detailed study of the reproductive habits of Rhinopoma kinneari (Wroughton) inhabiting a semi‐arid region of India (Jodhpur) was made to fill in the paucity of such information in the Family Rhinopomatidae.The reproductive pattern of Rhinopoma can be related to its seasonal movement which occurs just before and immediately after its winter torpor. The testes are permanently abdominal and these together with the accessory reproductive organs experience an annual sexual cycle. The females are monoestrous, breed in March and bring forth a single young during July‐August. Pregnancy lasts for at least 123 days and parturition occurs by head presentation. The young are weaned after six to eight weeks of suckling and attain sexual maturity in their second year of age.
The functional anatomy and histology of the alimentary canal of the maldanid polychaetes Clymenella torquata and Euclymene oerstedi
Authors: Pilgrim Muriel 
Published: August 2009

The alimentary canal of the maldanid polychaetes Clymenella torquata (Leidy), and Euclymene oerstedi (Claparède (=Caesicirrus neglectus Arwidsson, 1911) resembles, in many ways, that of the arenicolids. It is divided into buccal mass, pharynx, oesophagus, stomach and intestine, the three latter regions showing further subdivision. The buccal mass and anterior pharynx together form an eversible proboscis. The pharynx, oesophagus, and greater part of the intestine are ciliated. Simple feeding experiments, and histochemical tests, suggest that the stomach is concerned with the digestion and absorption of proteins, fats and carbohydrates, that the anterior intestine is a digestive and major absorptive region, and that the posterior intestine is a storage region. Waste materials are stored mainly in the wall of the oesophagus. A certain amount of intracellular digestion is carried out in the intestine of Euclymene but not in Clymenella. The difference is attributed to the richer, diatomaceous diet of Clymenella. British individuals of this species, being apparently selective feeders, differ not only from Euclymene but also from American ones, both of which ingest the substratum non‐selectively.The pharynx, oesophagus and rectum are surrounded by plexuses of blood capillaries, while the remaining regions are associated with a blood sinus system which varies in position and form in the different regions, lying deepest in the absorptive intestine. The gut muscle seems to be more concerned with moving the blood forward through the sinus system and into the anterior plexus than with moving the food backward. One region of the stomach musculature is especially concerned with this circulation. Rectal respiration probably occurs.
Structure and function in the catfish
Authors: Alexander R. McN. 
Published: August 2009

The catfish (Siluroidei) appear to have evolved from an ancestor which, in most respects other than the form of its teeth, resembled primitive Characinoidei. In the first part of this paper it is shown that most of the numerous and profound anatomical changes which have occurred in the course of their evolution from this ancestor can be related to one or other of three basic changes: depression of the body in adaptation to bottom‐feeding habits, sensory modification in adaptation to nocturnal habits, and the evolution of defensive fin spines. Diplomystes is more primitive than other known catfish in the form of its maxilla and pectoral girdle, and in the posterior position of its dorsal fin.The second part of the paper is concerned with some of the more specialized families of catfish (Mochokidae, Siluridae, Schilbeidae, Malapteruridae, Clariidae, Callichthyidae and Loricariidae). The specializations in each case are described, and related to the habits of the fish.
Identification of hair and feather remains in the gut and faeces of stoats and weasels
Authors: Day M. G. 
Published: August 2009

Qualitative analysis of the gut and faeces contents of stoates and weasels is complicated by the lack of readily identifiable bone fragments, teeth, feathers, etc., of mammalian or avian prey. Often the only evidence of such prey was hair or feather fragments. Since the bulk of food taken by stoats and weasels was from these two food classes, the problem of qualitative analysis resolved itself into that of identifying these hair and feather fragments.By using the scale pattern, cross‐section and medulla type, it was possible to construct a key which would identify guard hairs of small mammals of the generic level. Feather identification was based on the structural variations to the down barbules of coverts. Using such criteria a key to the main bird orders was devised.
New sharks from the South China Sea*
Authors: Chan W. L. 
Published: August 2009

Three new species and one new genus of sharks are described from the South China Sea. Cephaloscyllium fasciatum sp. n. (Scyliorhinidae) has a distinctive colour pattern characterized by the presence of dark‐edged blotches and saddles; and by the lobe‐like anterior nasal flap. The colour pattern and certain developmental changes in C. umbratile Jordan and Fowler are discussed. Dichichthys melanobranchus gen. n. and sp. (Scyliorhinidae) combines the distinguishing characters of three distinct genera: Galeus Rafinesque, Parmaturus Garman, and Apristurus Carman. This suggests that Dichichthys may be an ancestral form from which these three genera have evolved. Etmoptems decacuspidatus sp. n. (Squalidae) is distinguished primarily on the basts of the decacuspid teeth to the upper jaw; this unusually high number of cusps is shown not to have been acquired as a result of old age.The vertebral characters of all species are studied radiographically.
Relationships of the Hooded and Elephant seals (genera Cystophora and Mirounga)
Authors: King Judith E. 
Published: August 2009

The characters linking Mirounga and Cystophora in the subfamily Cystophorinae are the reduction of the incisors to 3/1, the nasal sac of the male, and also the general similarity in shape of the postcanine teeth. Because of the unreliability of dental characters, and the possibility of convergence producing the nasal sac, the entire skeleton and some soft parts of the body have been considered. This examination has produced 17 good characters in which Cystophora agrees with other northern phocids, and Mirounga with other southern phocids. Other characters confirming this division, but not considered trenchant enough for inclusion in the table, have also been found.It is suggested that the subfamily name Cystophorinae be abandoned. The family Phocidae is therefore divisible into two subfamilies; Cystophora being included in the Phocinae, and Mirounga in the Monachinae.Certain characters suggest that Erignathus and Monachus may be the forms linking the typically northern and the typically southern phocids.
The sense organs on the mouth parts of the Desert locust (Schistocerca gregaria)
Authors: Thomas Joan G. 
Published: August 2009

The “hairs” and various types of sensilla present on the mouth parts of Schistocerca gregaria are described. The distribution of the sensilla on the clypeo‐labrum, labium and theHmaxillae has been plotted in detail, and the general distribution of all types of sensilla on each of the mouth parts is described.A comparison is made between the distribution of certain sensilla on the clypeo‐labrum in first instars and adults.The probable role of the sensilla in feeding is discussed.
Feeding and digestion in two intertidal gammarids: Marinogammarus obtusatus and M. pirloti
Authors: Martin A. L. 
Published: August 2009

The diet of two intertidal species of gammarid, Marinogammarus obtusatus Dahl and M. pirloti Sexton and Spooner is described. Both species feed largely, but not exclusively, on decaying algae, but may eat some living algae and, more rarely, carrion.Their feeding activities are influenced by the rhythmic pattern of tidal ebb and flow, feeding only when covered by water. When immersed by the incoming tide they ingest food rapidly for a while and then feed more intermittently, ingesting small amounts at a time until they are uncovered once more by the receding tide. They probably eat sufficient food to fill the gut twice in 24 hours. The optimum rate for the digestion of food is approximately five hours, although food remains in the gut for about 12 hours.The pH of the contents of the proventriculus, digestive gland and intestine of M. obtusatus is distinctly acid. Digestive enzymes are secreted only by the digestive gland. Carbohydrases are present which will hydrolyse soluble starch, glycogen, sucrose, maltose, arbutin, salicin, raffinose and melibiose. Inulin, lactose and cellulose are not hydrolysed. Non‐specific esterase and true lipase were detected by histochemical methods.It is concluded that the food supply available to these animals is plentiful and it is unnecessary to utilize the food supply to the maximum.
Land molluscs as food of Malayan rodents and insectivores
Authors: Liat Lim Boo 
Published: August 2009

Laboratory and field experiments demonstrate that, contrary to previously published stomach analysis data, rats selectively consume land molluscs. Rattus jalorensis and R. argentiventer prefer molluscs as food, while R. exulans and R. r. diardi are less inclined to do so. Macrochlamys resplendens, a land snail, is most favoured, with the slug Micropar‐mariort malayanus next in preference. The heavily‐shelled Achatina fulica is only occasionally eaten and Quantula striata is ignored. Examination of gastro‐intestinal contents of wild rats caught from various habitats in Malaya show that when present in large numbers molluscs form an important part of the natural food of rats, yet laboratory evidence demonstrates that as many as 60% of mollusc‐eating rats may fail to show evidence of shells on examination within 12 hours of feeding–an indication that stomach analyses alone may be of limited value.The Malayan insectivores Echinosorex gymnurus and Suncus murinus often feed on snails and slugs, though they appear not to be suitable hosts for infection with the rat lungworm Angiostrongylus cantonensis.
Mole activity in woodlands, fens and other habitats
Authors: Mellanby K. 
Published: August 2009

Monks Wood, a deciduous wood of 155 hectares on clay soil, has an estimated population of 400 moles. There is an anastomosing system of permanent burrows, and when a mole is trapped its area of burrow is soon occupied by another animal. Little new digging occurs, except in winter, after frost has driven the soil fauna deeper into the ground. The burrows usually act as pit‐fall traps for the food. Young animals migrating in summer may live more superficially, in tunnels in moss and grass, but survivers usually move into a permanent tunnel system by autumn.Woodwalton Fen has an easily worked peat soil, and few earthworms. Here moles burrow at all seasons, presumably needing an extensive burrow system to catch sufficient food. In times of flood, the moles leave submerging ground but return very soon after the water subsides. They probably swim across flooded areas but iis yet we do not know if the same animals return after floods to the same burrows.Moles are not good indicators of soil fertility, particularly as many mole heaps are made by few moles in poor soil, and fewmew heaps may appear in good soil with permanent burrows. We do not understand why there are so few moles in some apparently suitable pasture, with high worm populations, or how others manage to obtain sutficient food in infertile areas.
Seasonal changes in the distribution of gonadal lipids and spermatogenetic tissue in the male phase of Monopterus albus (Pisces: Teleostei)
Authors: Chan S. T. H. , Phillips J. G. 
Published: August 2009

The gonad of Monopterus albus undergoes cyclical changes after the reversal of sex from female to male. The seasonally variable events include a prenuptial accumulation of cholesterol‐positive lipid droplets in the cytoplasm of the interstitial cells when spermatogenetic activity is resumed in late February and early March. The development of the interstitial Leydig cells reaches a maximum in May just before spawning. There occurs a sudden depletion of the interstitial lipids during the breeding season in June at a time when the male animals exhibit active nuptial behaviour. After spermiation, the old interstitial cells degenerate, and during the succeeding phase of gonadal inactivity, become replaced by a new generation from connective tissue cells in the interstitium of the gonadal lamellae which gradually accumulate lipoidal material.The lobular cycle comprises a postnuptial accumulation of amorphous intralobular lipids which become completely cleared in February when active spermatogenesis is restored. Spermatogenesis resumes shortly after spawning, but only advances as far as primary spermatocytes during the postnuptial period of inactivity.The authors conclude that, as far as the seasonal variations in gonadal lipid distribution is concerned, the cycles in the gonad of the hermaphroditic teleost, M. albus, conform to the same pattern as those of the gonochoristic seasonal breeders studied.
Gastric and duodenal differentiation in Erinaceus europaeus and its relationship to antibody absorption
Authors: Morris B. , Steel E. D. 
Published: August 2009

The stomach of the hedgehog is a simple sac‐like structure, and is divisible into three main regions based upon the histological structure of the gastric glands.Peptic cells containing prominent Bowie positive granules are present at the bases of the rudimentary gastric glands at birth. A mucinogen component persists in these cells until about three weeks after birth.Oxyntic cells differentiate from a non‐mucoid cell type, they are far less numerous than petic cells throughout the suckling period.Pepsin assays on the fundic mucosa reveal that pepsin is present in considerable amounts at nine days of age, and that near‐adult levels are attained by about the end of the fourth week. Gastric pH declines during the suckling period, from near neutrality at birth to generally between 3.0 and 4.0 during the fourth and fifth weeks. Proteolytic digestion of antibody is delayed not through lack of enzyme but because the hydrogen ion concentration is generally inadequate for its action.Evidence is presented to support the suggestion that the cessation of antibody absorption in the hedgehog and the rat is brought about, initially at least, by changes in the secretory activity of the gut, rather than by changes in the absorptive intestinal epithelium.
Muscular function and skull growth in the laboratory rat (Rattus norvegicus)
Authors: Moore W. J. 
Published: August 2009

Bilateral masseterectomy in newly‐born rats results in a diminution in cranial weight and size. Such reduction affects the facial skeleton to a greater overall extent than the braincase, although in each region it is the dimensions of length that are affected to a greater extent that are those of height or width. Such contrasts are not dependent upon changes in body weight.Removal of both temporal muscles—a smaller component of the masticatory musculature—results in little change in cranial proportions other than an increase in width of the braincase.Such findings can be related, first, to contrasts in the timing of growth in the braincase and facial skeleton and, second, to the extent to which muscular function is reduced.
Variation in the Long‐tailed field‐mouse (Apodemus sylvaticus) in south‐west england
Authors: Delany M. J. , Healy M. J. R. 
Published: August 2009

Measurements of four skull and five external characters were made on each of 277 specimens of Apodemus sylvaticus (L.) from the two Isles of Scilly (Tresco and St Mary's) on which it occurs and from six localities in mainland Cornwall. The skull characters were greatest length of skull, maxillary tooth row, cranial breadth and length of palatal foramen. Lengths of the pectoral stripe, tail, hindfoot and ear were obtained, as well as the weight of each animal. The age of each individual was assessed by means of a tooth wear character and a regression adjustment was used to bring all the characters to a uniform age class. The adjusted and unadjusted means have been calculated of each character for every locality. The sexes were separate throughout the analysis.The island mice are slightly larger than those from the mainland, the latter forming a fairly homogeneous group. In addition to overall size the most distinctive sign for the Tresco mice is the particularly small pectoral stripe. The St Mary's mice have a long tooth row, large pectoral stripe and large palatal foramen. The females were usually slightly smaller than the males.A canonical analysis was made in an attempt to account for as much variation as possible between groups using a limited number of linear combinations of the original measurements. The greater part of the variance was contained in the first two canonical variates. From these, the populations separated into three groups, i.e. the mainland group, the mice from Tresco and those from St Mary's. The two Scilly Island populations are as distinct from each other as they are from the mainland populations. Separate introductions from different sources and, possibly, slightly different genetic composition of the original immigrants may have accounted, in part, for the divergence shown by these two island stocks. It is not proposed that the island races should be given subspecific status.
Experiments on aggregations of Phymateus purpurascens (Orthoptera, Acrididae, Pyrgomorphinae)
Authors: Rowell C. H. Fraser 
Published: August 2009

Phymateus purpurascens Karsch has been studied in the wild and in captivity in Uganda. Its habits, colouration, behaviour and life cycle are described.All individuals are attracted towards each other by visual stimuli, and a moving individual is more attractive than a stationary one. This behaviour is unchanged by several instars in isolation. The aggregated larvae tend to move in synchronous bursts. and it is suggested that this is due to retinal image stabilization by an optomotor reflex.In an open field all instars are attracted towards isolated vertical objects in the visual field. This, together with the interindividual visual responses described, produces columns of moving insects. No olfactory communication could be demonstrated.Adults and larvae behave similarly in experimental situations; this contrasts with the observed dispersion in the wild with increasing age. It is suggested that dispersion results from loss of visual contact, caused by (a) loss of the conspicuous larval colouration, (b) chance isolation, and (c) increased mobility of fledged adults. The possible biological function of the gregariou habit is discussed, and the significance of the various colour patterns of the life history as inter‐and intraspecific signals.
Carotenoids and carotenoid metabolism in Carcinus maenas (Crustacea: Decapoda)
Authors: Gilchrist Barbara M. , Lee W. L. 
Published: August 2009

The carotenoid pigments of the hepatopancreas, ovaries and epidermis of Carcinus maenas were investigated. The following pigments were identified: β‐carotene, δ‐carotene, echinenone, isocryptoxanthin, canthaxanthin, lutein, zeaxanthin, flavoxanthin and astacene.The relative abundance of these pigments in the three tissues and the presence of possible hydroxy and keto intermediates suggest the metabolism of astaxanthin from β‐carotene. The metabolic pathway in Carcinus is discussed in relation to recent studies on other invertebrates.
The distribution and variation of Daphnia lumholtzi (Crustacea: Cladocera) in relation to fish predation in Lake Albert, East Africa
Authors: Green J. 
Published: August 2009

In Lake Albert Daphnia lumholtzi is found in two forms. One has a pointed anterior prolongation, or helmet, on the head. The other has a shorter rounded head, and was originally described as a separate species, D. monacha. The latter form dominates the zooplankton in the middle of the lake where planktivorous fish are rare or absent. The helmeted form becomes commoner near the margins of the lake and reaches its greatest abundance in Ndaiga Lagoon, where planktivorous fish are common. The possession of a helmet is associated with a reduction in the size of the carapace compared to the round headed form. The carapace with its contained eggs is the most conspicuous part of a cladoceran, so that the helmeted forms are at an advantage in the presence of planktivorous fish which locate their prey by sight. The mid‐lake monacha forms are larger than specimens of the same form in Ndaiga Lagoon, where it is shown that Alestes baremose feeds selectively on the larger specimens of the monacha form.The helmeted form produces more, but smaller eggs than the monacha form. The total brood volume (= mean egg volume x mean number eggs per female) is greatest in the midlake monacha forms. The selective advantages of variations in egg size and the possession of a helmet are discussed. It is concluded that the data from Lake Albert support the hypothesis of Brooks (1965) concerning the adaptive significance of helmet development in Daphnia.
The relationship of the mantle and shell of the Polyplacophora in comparison with that of other Mollusca
Authors: Beedham G. E. , Trueman E. R. 
Published: August 2009

The structure and growth of the polyplacophoran shell, characteristically consisting of eight plates surrounded by a girdle, is examined in the light of current views on the relationships of mantle and shell in the Bivalvia. The periostracum and outer and inner calcareous layers of the shell of the latter group are homologous with the cuticle, tegmentum and articulamentum respectively of the shell of the Polyplacophora. The margin of the mantle consists of a large marginal fold, which secretes the cuticular girdle, and a small accessory fold bearing mucous cells. These are functionally comparable with all three folds of the mantle margin found in other molluscs, although anatomically the marginal fold of the chitons probably represents only the inner surface of the outer fold of the mantle margin.The cuticle not only forms the girdle, which bears calcified spines or spicules, but also extends between the shell plates. The principal part of the cuticle consists largely of mucopolysaccharide material but there is also a thin discrete inner region which is similar chemically to the periostracum of other molluscs. The cuticle, possibly without spines, probably covered the entire dorsal surface of a primitive placophoran and beneath this, plates developed. As these grew the cuticle became worn away except marginally and between the plates. It is suggested that a covering of mucus over the visceropallium may have been the forerunner of the molluscan shell and the possible evolutionary relationships of the shell throughout the Mollusca are discussed.