bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth and development of Taonius megalops (Mollusca: Cephalopoda), and some phases of its life cycle
Authors: Dilly P. N. , Nixon Marion
Published: August 2009

Taonius megalops is a neutrally buoyant oceanic squid, very different in form when young and old. The young, has a round, sac‐like mantle and relatively long tentacles, while the adult has an elongated cone‐like mantle and relatively short tentacles. The transition in shape and form is gradual and has been followed in animals of between 3 and 180 mm dorsal mantle length. Statistical tests on various parameters investigated, both external and internal, revealed good correlation with the dorsal mantle length and confirmed the descriptions of the development of the chromatophores and subocular light organs with growth. It was concluded that these animals, captured in the Atlantic Ocean, all belonged to the species T. megalops Prosch 1849. This study has permitted us to suggest a tentative outline of the life cycle, although no adults were present in the material available.
The ultrastructure of the heart and kidney of the pilid gastropod mollusc Marisa cornuarietis, with special reference to filtration throughout the Architaenioglossa
Authors: Andrews Elizabeth B.
Published: August 2009

Transmission and scanning electron micrographs of the heart and kidney of Marisa cornuarietis (L.) reveal that the auricle is largely responsible for filtration supplemented to a small extent by the ventricle. The epicardial cells of the auricle are specialized to allow the escape of a filtrate of the blood, but do not bear any resemblance to podocytes. The posterior part of the kidney is lined by a characteristic renal epithelium excreting uric acid and resorbing glucose whilst the anterior part has an epithelium specialized for active transport of ions. A possible mechanism for filtration is suggested, and the functional significance of the structural variations in the heart and kidney of pilids, viviparids and cyclophorids is discussed.
Seasonal changes in the testis and epididymis of the American Grey squirrel, Sciurus carolinensis
Authors: Pudney Jeffrey
Published: August 2009

The histological changes in the testis and epididymis of the American Grey squirrel, Sciurus carolinensis (Gmelin) during development and the testicular cycle are described. It was observed that male Grey squirrels, as a population, did not undergo a pronounced seasonal reproductive cycle, however, individual males did experience periods of reproductive inactivity which were asynchronous and not related to seasonal changes in the environment. It is suggested that the individual sexual cycles are due to an endogenous rhythm of gonadotrophin secretion by the pituitaries of these animals.
Some aspects of the morphology of Blue tits (Parus caemleus) and Coal tits (Parus ater) in relation to their behaviour
Authors: Partridge Linda
Published: August 2009

An attempt is made to find functional relationships between the morphology of titmice and their behaviour. Coal tits have relatively longer feet than Blue tits, and they also have relatively long back claws and toes. This may be related to life in pine needles, the long Coal tit feet having an effect analogous to snow shoes. Blue tits, in contrast, have short strong toes which are opposable, and this may enable them to hang on oak leaves. There are small but consistent differences in leg length and proportions between Blue, Coal, Marsh and Great tits. These differences do not seem to be related to behaviour in the same way as in any other bird group. Coal tits have wings of higher aspect ratio than Blue tits, and they also have a lower wing loading. This may be related to the superior hawking and hovering ability of Coal tits. Coal tits have longer and finer bills than Blue tits, and this may be associated with small prey size and probing into crevices for food. A fine bill would be of advantage when dealing with small prey, but a long bill would be a handicap for seeing small prey close to the bill tip.
Nematode growth patterns and the moulting cycle: the population growth profile
Authors: Wilson Peter A. G.
Published: August 2009

Population growth profiles of Caenorhabditis elegans and Panagrellus redivivus constructed from length frequencies have a number of steps in them coinciding with the number of extrauterine moults. Each step has a constant size relationship with that of one of the midmoults measured directly.

The profiles could only have the shape they do if there are corresponding steps in the true growth curve of individual worms: the fact that previous workers have been unable to detect these steps being due to the limitations of techniques available for the study of synchronous and individual growth curves. Nevertheless, a synchronous system with Trichostrongylus retortaeformis gives qualitative support to the findings from population profiles.

The population growth profile is a new tool in the study of environmental effects on moulting, though there are theoretical reasons why the true growth curve cannot be derived from it.

Abandonment of the “continuous growth” model for post‐embryonic development simplifies the framing of hypotheses to explain ecdysis in nematodes.
Defaecation in the stem nematode, Ditylenchus dipsaci
Authors: Doncaster C. C. , Seymour Malcolm K.
Published: August 2009

The process of defaecation in the stem nematode, Ditylenchus dipsaci, has been analysed using cinemicrography. During feeding regular shortenings of the hind end of the body are accompanied by groups of a few defaecation periods. Each period begins as the shortened hind body re‐elongates, and consists of several defaecation cycles. In each cycle the posterior rectum becomes dorsally bowed and, as it straightens, the rectal valve, rectum and anus open. Faeces pass out irregularly while the rectum remains open and are forcibly expelled as it closes. Defaecation in D. dipsaci is intermediate between that of the high‐pressure nematode Aphelenchoidzs blastophthorus and the low‐pressure passive feeder Hexatylus viviparus. We suggest that the main function of defaecation in plant nematodes is to excrete excess water.
The nature and basis of sexual dimorphism in the primate skeleton
Authors: Wood B. A.
Published: August 2009

This study sets out to document and analyse sexual dimorphism in the teeth and bones of five primate groups, including man. Specimens were only included in the analysis if their sexual attribution was reliable and was based on non‐osteological criteria. Ninety raw measurements, both cranial and post‐cranial, were used and 11 indices were computed from them.

The parameters of each sample were computed in order to compare these results with previous estimates of dimorphism which have not always been based on reliably sexed samples. Correlation matrices were computed.

The overall sex differences were subdivided into “shape” and “size” components using Penrose's size and shape distances and by computing the principal components of each data set. The visually apparent shape differences were confirmed metrically and then examined to see whether they could be explained by allometric effects or whether there was evidence for sexual differences in growth patterns.

Using femur length as the independent variable, because of its correlation with overall size, allometric coefficients were computed for the logarithmically transformed data. The coefficients were in some cases very different between sexes but the majority did not achieve statistical significance. Of those that were significantly different only in Homo did such differences narrowly exceed the number that would be expected by chance alone.

As the vast majority of allometric coefficients for the pooled male and female data differed from unity, the hypothesis that most of the considerable shape differences that exist between some male and female primates are due to underlying growth differences must be rejected. It is suggested that such differences are simply the result of disproportionate change in size.
Possible significance of the red patches of the female crab‐spider, Misumena vatia
Authors: Hinton H. E.
Published: August 2009

The female of the crab‐spider, Misumena vatia, is one of the few spiders known to be able to change its colour reversibly. Adult females usually have red patches on each side of the abdomen. The most likely insect enemies of Misumena are red‐blind, and because the red patches absorb ultraviolet exactly as does the rest of the abdomen the patches are not distinguishable to insects in the ultraviolet. It is suggested that the red patches function as a warning colour for birds and other vertebrates, which are not red‐blind.
Leverage and muscle type in crab chelae (Crustacea: Brachyura)
Authors: Warner G. F. , Jones A. R.
Published: August 2009

The chelae of Cancer pagurus and Macropipus depurator were examined with respect to mechanical advantage. The closer muscles were investigated with respect to sarcomere length in the constituent fibres and to the force developed by the whole muscle during isometric contraction. Cancer chelae have a relatively high mechanical advantage, 0.329 ± 001. Cancer closer muscles contain a high proportion of fibres with long sarcomeres, mean lengths mostly falling between 12 and 15 μm, and develop a maximum stress of about 496 kN.m−2 during contraction. These figures are typical for “slow” crustacean muscle. The chelae of M. depurator are dimorphic. In one, the strong chela, the mechanical advantage is 0.248 ± 0.066 while in the other, the fast chela, the mechanical advantage is 0.177 ± 0.006. M. depurator closer muscles contain fibres with mean sarcomere lengths mostly falling between 6 and 10 μm. The muscle develops a maximum stress of about 145 kN.m−2 during contraction. These figures are typical of “intermediate” crustacean muscles. “Fast” muscle fibres with short sarcomeres (about 30 um) were found in the chelae of both Cancer and M. depurator but were much commoner in the latter. Thus in Cancer a high mechanical advantage is correlated with slow muscle while in M. depurator lower mechanical advantages are broadly correlated with faster muscle. Consistent correlation between mechanical advantage and muscle type in the dimorphic chelae of M. depurator, however, is lacking. No consistent regionation of fibres with similar properties was found in the muscles.
A new and eyeless cobitid fish (Pisces, Cypriniformes) from the Zagros Mountains, Iran
Authors: Greenwood P. H.
Published: August 2009

The first blind, and colourless, noemacheiline cobitid fish is described and compared with other cave‐dwelling species of the subfamily. The new taxon, recently discovered in a natural well connected with subterranean waters in the Zagros Mountains of Iran, coexists with the blind depigmented cyprinid fish Iranocypris typhlops discovered in 1937. Some consideration is given to the generic status of the new species and its relationships to other noemacheilines.
Daily variations of behavioural activities and of plasma testosterone levels in the domestic duck Anas platyrhynchos
Authors: Balthazart J.
Published: August 2009

The daily variation of various behavioural activities and of plasma testosterone levels have been studied simultaneously in two groups of five domestic ducks. The social displays and sexual behaviour are essentially exhibited by the birds during the early morning (and to a lesser extent in the late afternoon for major displays). The morning corresponds precisely with the highest testosterone levels observed in the blood. As testosterone propionate injections are known to elicit social displays and sexual behaviours in ducks, it is suggested that the correlation observed between the variations of testosterone levels and of behaviour could be due to a direct effect of the variations of hormone levels on behaviour. The theoretical possibility of such a short‐term hormonal effect is briefly discussed.
Some observations on the infrastructure of the thyroid of certain Cervidae
Authors: Young B. A.
Published: August 2009

The thyroids of four species of deer were examined with the electron micriscope and the appearance of the follicular cells are described. In particular phagolysosomes are described in relation to the secretion of thyroid hormone.
The tracheal arrangement and the classification of linyphiid spiders
Authors: Blest A. D.
Published: August 2009

The tracheal arrangement of 121 species of European Linyphiidae has been examined. Tracheal systems support the division of the family into two major groups: Linyphiinae have four simple tracheae arising from the spiracular atrium which are confined to the abdomen, whilst Erigoninae have large medial trunks which divide into numerous small branches before passing as two bundles through the pedicel to the prosoma, and short, simple lateral tracheae. In the majority of Erigoninae the medial branches are without taenidia and can be regarded as tracheoles but in Hilaira, Donacochara, Leptorhoptrum and Drepanotylus the branches possess taenidia. Allomengea is anomalous in that the medial tracheae are extensively branched but remain confined to the abdomen. Carorita, Mioxena, Wiehlea, Lessertiella, Jacksonella, Asthenargus, Aphileta and Ostearius, which have been regarded as Erigoninae on the grounds of genital anatomy, all possess linyphiine tracheal systems. The significance of these findings is discussed.
A review of the genus Capitella (Polychaeta Capitellidae)
Authors: Warren Lynda M.
Published: August 2009

The genus Capitella is reviewed and eight species are recognized, with two subspecies. Redescriptions are given where appropriate. The relationship of the genus to other capitellid genera is discussed and Capitellides is united with Capitella and the resulting new combinations given. The value of stereoscan microscopy techniques as a taxonomic tool is discussed.
An electron microscope study of the formation of the periostracum in the freshwater bivalve, Anodonta cygnea
Authors: Bubel Andreas
Published: August 2009

The periostracum and cells lining the periostracal groove of Anodonta cygnea L. have been studied at the electron microscope level. The cells lining the inner face of the outer fold differ in fine structural details, five cell types being recognized. Along the length of the outer surface of the middle fold, to which the periostracum is closely applied, only two cell types are evident. At the base of the periostracal groove the two epithelia are separated by a bulbous region containing a group of basal cells which initiate the periostracum. The periostracum, which is homogenously electron‐lucid, originates in the intercellular space between a basal cell and the first cell of the middle fold. It increases in thickness in the periostracal groove due to the secretory activity of the different outer fold cells. The cells of the middle fold do not appear to be involved in periostracum formation.
A further description of the echiuran Prashadus pirotansis
Authors: Hughes Roger N. , Crisp D. J.
Published: August 2009

The echiuran Prashadus pirotansis is redescribed from new material collected in the Arabian Gulf. The description greatly amplifies that of Menon & Datta Gupta (1962) and reveals an error in their original description of this species. Information is provided on habitat, zonation and feeding activities.
The buoyancy and orientation of the upside‐down catfishes of the genus Synodontis (Pisces: Siluroidei)
Authors: Willoughby N. G.
Published: August 2009

The forces involved in the buoyancy of the genus Synodontis are unusually large owing to the well‐developed cephalo‐nuchal shield possessed by all members of the genus, and the large swim bladder and high levels of body fat needed to counteract this. A new method of determining the quantity of crude lipid in the tissues was developed and tested against a recognized method. Negative correlations were found between the total quantities of fat present and the volumes of the swim bladder for several species. Two species which maintained neutral buoyancy but occupied different ecological niches were found to achieve neutrality by different means, one possessing an abnormally large swim bladder and the other very large quantities of fat. The amount of bone present was found to be considerably greater than in species from other genera.

Several species of this genus regularly invert and swim on their backs. Three of the species known to do this were found amongst the 16 species present in the man‐made Lake Kainji on the River Niger in Nigeria. The orientations of many of the species were studied both under natural conditions and in the laboratory. Several possible causes of inversion were investigated, including both physical and behavioural factors. The position of the food source was found to be the most important factor controlling the orientation of the species. By manipulating this it was possible to persuade normally orientating species to invert, and inverting species to return to normal orientation. Three theories to explain the inverting habit are advanced and their merits discussed.
Ecological studies on Indonesian lakes. Overturn and restratification of Ranu Lamongan
Authors: Green J. , Corbet S. A. , Betney) E. Watts (née , Lan Oey Biauw
Published: August 2009

In July 1974 Ranu Lamongan overturned. The resulting deoxygenation of this small tropical crater lake killed some of its fishes. This paper describes the recovery of stratification of temperature and oxygen and follows short‐term changes in the plankton during the three weeks after overturn. The lake is fringed with a floating mat of Eichhornia whose submerged roots support and shelter a rich community of invertebrates on which much of the fishery depends. Comparison of our findings with those of the German Sunda Expedition in 1928 show remarkably few changes in the lake or its biota during the 45‐year interval, despite a marked increase in the human population and the introduction of four species of fishes.
The determination of age and growth from the scales in Barbus liberiensis (Pisces, Cyprinidae)
Authors: Payne A. I.
Published: August 2009

The predictability of scale check formation in Barbus liberiensis has been investigated. Scale length is shown to be linearly related to body length. The formation of the check can be interpreted in terms of the reproductive cycle and changes in somatic condition. Throughout the population check formation takes place in two phases, resorption of material from the scale edges coinciding with the early and middle phases of gonad maturation, and the formation of the check itself as a result of repair as maturation is completed. Check formation is not correlated with actual spawning activity and fluctuations in food intake and temperature are insignificant.

The first scale check is formed at the end of the first year and from analysis of check frequency the mean body lengths at the end of the first, second and third years were 6·9 cm, 8·3 cm and 9·3 cm. There was no significant difference in the growth rate of males and females although the females tend to live longer and therefore attain a greater maximum size. Some individuals may not have formed a check at the end of the first year.

The difference between check formation in tropical and temperate fish and also between forest and savanna types are discussed. The predictability and the factors affecting check formation in tropical freshwater fish are considered.
The effect of odour on trap response in Microtus townsendii
Authors: Boonstra Rudy , Krebs Charles J.
Published: August 2009

To investigate trap response of Microtus townsendii we set dirty Longworth traps soiled with faeces, urine and other debris and clean Longworth traps washed in hot water in field plots. Voles entered dirty traps significantly more than clean traps. This result was more pronounced in new animals and in young animals. When all clean or all dirty traps were set on a field plot, a much larger proportion of the animals known to occur on an area were caught in dirty traps than were caught in clean traps. This effect was most pronounced in the summer and fall period and was strongly correlated with the presence of breeding females.
Cephalopod remains from the stomachs of Sperm whales caught off Peru and Chile
Authors: Clarke M. R. , MacLeod N. , Paliza O.
Published: August 2009

One thousand cephalopod lower beaks from random samples of the stomach contents of four Sperm whales caught off Peru and Chile are identified and/or described. Non‐random samples of stomach contents from 10 whales were also examined. The size of the lower beaks is used to estimate the mean and the total weight of the cephalopods of each taxon identified. The three most numerous species are Histioteuthis sp. i (50%), Chiroteuthis sp. A (16%) and Octopoteuthis sp. (9%) while the greatest weight of flesh is contributed by Histioteuthis sp. A1 (56%), Dosidicus gigas (32%) and Vampyroteuthis infemalis (3%). Lower rostral length frequency distributions are compared with those that have been constructed for other regions. Antarctic species of cephalopods represented by beaks show that two female and one male whale probably moved north from much further south immediately prior to being shot off Peru in November, December and February.
The fleas of a population of weasels in Wytham Woods, Oxford
Authors: King Carolyn M.
Published: August 2009

Weasels were regularly livetrapped, anaesthetized and searched for fleas over two years, in Wytham Woods, near Oxford. Eleven species of fleas were identified among 262 collected. Seven normally occur on small rodents, one on rats, two on moles and one on birds. Fleas were collected on 103 of 338 occasions when an unconscious weasel was examined; on average males carried 0·6 fleas, females 1·5 fleas, but there was no significant difference between the proportion of males and females infested. The species distribution of the fleas on weasels in Wytham suggests that they acquire their fleas mainly from the nests and runways of their prey, which they have hunted through or taken over. Important prey, e.g. birds (22% of prey items identified) with uninviting nests contributed few fleas (2%); non‐prey, e.g. moles (0–4% of items) with highly desirable nests, contributed disproportionately many, including 35 fleas (15%) of two species otherwise monoxenous on moles. A similar pattern is shown by the fleas carried by stoats in New Zealand.
Seasonal coat changes in grazing Red deer (Cervus elaphus)
Authors: Ryder M. L.
Published: August 2009

Seasonal change in the coat of four male and four female Red deer (Cervus elaphus) was studied in coat and skin samples taken monthly for two years. Changes in coat length were measured, the times of moult recorded, and the cycle of follicle activity determined from histological preparations.
Studies on the skull of the Henophidia (Reptilia: Serpentes)
Authors: Rieppel Olivier
Published: August 2009

The skulls of Cylindrophis, Anilius, Uropeltis and other genera of Uropeltidae, Xenopeltis and Loxocemus are described and figured.

On the basis of cranial characters, a separation of the Aniliidae into two subfamilies, the Aniliinaeand theCylindrophinaeis suggested. The Uropeltidae, separated from the Aniliidae by a set of derived characters, are grouped together with the Aniliidae as the superfamily Anilioidea. The skulls of Xenopeltis and Loxocemus are described and the systematic position of the genera discussed. General remarks as to the bearing of the skull on the reconstruction of henophidian phylogeny conclude the study.
The biology of a giant dung‐beetle (Heliocopris dilloni) (Coleoptera: Scarabaeidae)
Authors: Kingston T. J. , Coe Malcolm
Published: August 2009

Heliocopris dilloni is the largest dung‐beetle found in the Tsavo National Park, Kenya, which during the biannual rainy seasons comprises the most important agency of elephant dung removal. The species is shown to exhibit considerable morphological variation. The mode of construction of the brood chamber is described together with details of development from egg to pupa. It is suggested that the depth to which these beetles burrow is related to avoiding the extreme climate near the surface and to predator avoidance.
Terrestrial locomotion in two species of amphibian larva
Authors: Oldham R. S.
Published: August 2009

Leptopelis hyloides and Chiromantis rufescens, which deposit eggs out of water, are compared with the aquatic breeding Bufo maculatus in terms of the ability of their larvae to move on land. Leptopelis larvae travelled further, faster and in a more consistent direction than Chiromantis larvae; they also survived better on land. Bufo larvae showed no terrestrial locomotion. These facts are related to the breeding behaviour of the three species. Locomotory ability in both Leptopelis and Chiromantis larvae was influenced by relative humidity and in Leptopelis the direction of movement was apparently influenced by topographic gradient and by the position of the closest standing water.
A preliminary investigation into Natterjack toad (Bufo calamita) breeding site characteristics in Britain
Authors: Beebee TrevorJ. C. , Griffin JohnR.
Published: August 2009

A routine was established for sampling pH in aquatic environments which permitted assessment of an “average site pH”±0.5 units by measuring that of a single sample at any time of year. Requisites for accuracy were that samples should be taken in clear water away from weed, and at least three days after significant rainfall.

pH measurements were taken in a number of ponds and compared with the use of these waters for breeding purposes by Common toads (Bufo bufo) and frogs (Rana lemporaria). Toads were found breeding in water slightly more acid than those tolerated by frogs. Similar measurements of pond pH in dune and heath habitats frequented by Natterjack toads (Bufo calamita) were compared with breeding site choices by these anurans. A marked avoidance of acid waters was evident in the predominantly acid heathland habitats. This was probably not directly related to the concentrations of inorganic ions in the pools.

Development of Rana lemporaria, Bufo bufo and B. calamita spawn under various pH conditions was examined. Survival rates were optimal in the pH ranges found to be chosen in the wild, and no differences were observed between Bufo calamita spawn taken from dune or heathland populations. Developmental abnormalities in the tadpoles were more frequent under acid conditions.

A preliminary study of ponds used by the three species of anurans native to Britain was carried out by measuring pH with a tested field procedure. Differences between Bufo bufo and Rana temporaria breeding sites were not significant on the basis of pH in the areas studied, but B. calamita populations on heathland were found to avoid the acid pools. The field data correlated well with the pH tolerance of the anuran larvae reared in captivity. The significance of these findings is discussed.

The authors wish to thank Dr A. Cooke (Institute of Terrestrial Ecology) and Dr D. Sutcliffe (Freshwater Biological Association) for analyses of selected water samples; Mrs M. Beebee for statistical treatment of the data; and the Carnegie (U.K.) Trust for financial support.
Further background‐choice experiments on cryptic Lepidoptera
Authors: Kettlewell H. B. D. , Conn D. L. T.
Published: August 2009

Background choice experiments were performed using polymorphic night flying moths common in Britain and emerging at different times of the year. Such species have to spend their daylight hours motionless at rest on their correct backgrounds. Significant differences were found between the site preferences of different morphs of the same species. The morphs chose backgrounds most appropriate to their colouration.
A new family of astigmatid mites from the lies Crozet, sub‐Antarctica; introducing a new concept relating to ontogenetic development of idiosomal setae
Authors: Griffiths D. A.
Published: August 2009

Glycacarus combinatus
gen. and sp. nov. was collected from the nest of the White chinned petrel (Procellaria aequinoctialis) on Possession Island Sub‐Antarctica. It can be distinguished from all other members of the Astigmata by the M‐shaped prodorsal shield and by the fact that it is made up of a complete mixture of the morphological characters which separate the Glycyphagidae from the Acaridae. In order to maintain the present familial structure within the free‐living Astigmata a new family Glycacaridae is proposed. It is suggested that these three families arose from three evolutionary lines which separated from a common ancestor possibly during the Cretaceous period. Ontogenetic development of the body setae is described and a new interpretation of setal homologies relative to different life‐cycle stages is discussed, together with a revised nomenclatural system for the idiosomal seta.
Structural observations on the alimentary canal of Paranthessius anemoniae, a copepod associate of the snakelocks anemone Ammonia sulcata
Authors: Briggs R. P.
Published: August 2009

Light and electron microscopy has shown the alimentary canal of Paranthessius to be composed of clearly defined foregut, midgut and hindgut regions. The spacious foregut is cuticle‐lined and separated from the midgut by a valve. The midgut epithelium is composed of columnar cells with an apparent secretary/absorptive rôle, and amoeboid cells thought to engulf material from the lumen. The amoeboid cells have large electron‐dense central vacuoles containing carbohydrate‐and protein‐staining material. These cells appear to be sloughed off into the lumen to form part of a faecal pellet. Apart from their digestive rôle the midgut cells store lipid and it is considered possible that they have an osmoregulatory function. The hindgut epithelium cell type, lacks a cuticular layer and is thought to be mainly concerned with absorption. The alimentary canal is surrounded by strands of longitudinal and circular muscle.
Studies on the Red band fish, Cepola rubescens
Authors: Atkinson R. J. A. , Pullin R. S. V. , Dipper F. A.
Published: August 2009

The burrows of the Red band fish, Cepola rubescens L. are described from casts taken in situ using polyester resin. Observations of behaviour and spatial distribution are presented and the coloration, morphology, age, gonad condition and diet of captured specimens are discussed.
Mutual synchronization of diurnal activity rhythms in groups of Red wolf/coyote hybrids
Authors: Roper T. J. , Ryon J.
Published: August 2009

Two packs of Red wolf/coyote hybrids (ancestral species Canis niger and C. latrans), each consisting of three males and two females, were observed around the clock (a) when the males and females of each pack were housed in separate enclosures, and (b) when the males and females of each pack were reunited. The animals lived in outdoor enclosures under natural lighting conditions, and the period of separation by sex lasted for three months. The activity rhythm was typically bimodal with peaks at dawn and dusk, and total activity was greater during the day than during the night. The activity rhythms of all four single‐sex groups differed significantly from one another during the period of separation, but the differences between the sexes within each pack were reduced when the animals were reunited. We conclude that the activity rhythms of the members of each cohabiting group or pack tended to be mutually synchronized by means of social zeitgebers generated within the group. In addition, however, the data suggest that reuniting the sexes resulted in greater uniformity of activity rhythms between the packs, implying that the social structure of the pack may also have altered the responsivity of the members to external zeitgebers (time‐setters). Activity budgets showed that about 80% of total time was spent resting or in the den, and about 17% in general locomotion.
Behavioural ecology of the Sloth bear (Melursus ursinus)
Authors: Laurie Andrew , Seidensticker John
Published: August 2009

The Sloth bear (Melursus ursinus), which is endemic to the Indian subcontinent and Sri Lanka, has declined in numbers in many areas in recent years probably as the result of over‐killing and habitat alteration. In the 544 km2 Royal Chitawan National Park in the Nepal terai, we estimated there were a minimum of 55 bears or a crude density of 0˙1/km2. During peak concentrations in the lowlying riverine forest/tall grass habitat in March, the ecological density was 0˙5/km2.

Cubs still with their mothers comprised 24 % of the 161 bears classified between December 1972 and November 1975. Females comprised 48% of the adults classified. Average size of 24 litters was 1˙6 (1–2). Seventy‐two per cent of the observations were of lone individuals. Three (an adult female with two cubs), was the largest group of bears seen. The only extended social group observed was the female‐young unit although newly independent siblings may remain together for a short time. Maternal relations, adult interactions, tree marking, ranging, feeding and anti‐predatory behaviour are described.

Examination of 139 droppings showed that these bears fed on at least 17 different fruits (47% occurrence), flowers, grass, honey, and six different insects (52% occurrence). Fruits were an important food from March to June with individual species predominating throughout their fruiting season. Termites, including Odontotermes obesus, were in the diet for most of the year. The Sloth bear was not observed preying on mammals and according to other observers, only rarely feeds on carrion. The ecological basis for selected aspects of Sloth bear biology and behaviour is discussed.
On some species of Chonopeltis (Crustacea: Branchiura) from the rivers of the extreme South West Cape region of Africa
Authors: Fryer Geoffrey
Published: August 2009

Two new species of Chonopeltis (Crustacea: Branchiura), parasitic on cyprinid fishes, are described from rivers in the extreme S.W. Cape region of Africa. These emphasize the remarkable nature of the fauna of these rivers, which includes several endemic fishes. Like their hosts these closely related parasites came from the north and have close affinity with a species from the Orange River system. Their probable evolutionary history is discussed. Keys to both sexes of all described species of Chonopeltis are given.
The veliger larva of Hydrobia ulvae with observations on the veliger of Littorina littorea (Mollusca: Prosobranchia)
Authors: Fish J. D. , Fish Susan
Published: August 2009

The veliger larva of Hydrobiu ulvue (Pennant) from the west coast of Wales is described and illustrated from veligers hatched in the laboratory and collected in plankton samples. The larvae are planktotrophic and it is estimated that the pelagic phase is of about four weeks duration. In terms of density they form an important constituent of the plankton of inshore waters. The veliger larva of Littorina littoreu (L.) is also described and illustrated, and it is suggested that some of the conflicting reports on the length of the pelagic phase of H. ulvae result from confusion in indentification of the larvae of these two species.
The walk of the Silver gull (Larus novaehollandiae) and of other birds
Authors: Dagg Anne Innis
Published: August 2009

A total of 317 steps of walking Silver gulls (Larus novaehollandiiae) and filmed sequences of 24 other species of medium‐sized and large birds were analyzed. The angles made by the tibiotarsus‐tarsometatarsus joint of each leg during walking were measured. These varied depending on the species. In the Silver gull, where the angles were correlated with speed, the leg bent more sharply the slower the step; otherwise the angles were not correlated with speed. In all but the four largest birds, as in man, the leg was more bent in the middle of its stance phase than it was at the beginning or end of this phase. Thejoint was never completely straight, or 180″. In general the larger the bird, the slower was its step. The Silver gull and other birds do not bob their heads back‐and‐forth as they walk, but many birds do. It is not known why some birds bob their heads, although it may be correlated in part with a relative horizontal body posture, with seeing effectively, with balance during locomotion, or with habitat. The Silver gull does not hop, but some birds do, usually birds that live in the bush, or that are small.
The response of the freshwater gasteropods Lymnaea tomentosa and L. columella to desiccation
Authors: Harris R. E. , Charleston W. A. G.
Published: August 2009

At a constant temperature and humidity there was a linear relationship between the log of survival time and the log of shell length in Lymnaea tomentosa and L. columella. Reasons are suggested for this relationship. There was no significant species difference in ability to resist desiccation, provided specimens of either species were of similar shell‐length.
Changes in haemopoietic sites during the metamorphosis of the lampreys Lampetra fluviatilis and Lampetra planeri
Authors: Percy Richard , Potter I. C.
Published: August 2009

An investigation has been made in both the parasitic lamprey Lampetra fluviatilis and in its non‐parasitic derivative Lampetra planeri of the rate at which the fat column replaces the typhlosole and nephric fold as the principal site of haemopoiesis. In the typhlosole, blood cell formation started to decline prior to the onset of external metamorphosis and had ceased within four weeks of the commencement of transformation. In the nephric fold haemopoiesis continued for several weeks in the region where the larval opisthonephros persisted but was never observed in the newly developing adult kidney. Soon after the onset of external metamorphosis the fat column started to become haemopoietic and later became the main site of blood cell formation. The rate at which the haemopoietic function was transferred from the nephric fold and typhlosole to the fat column was greater in L. fluviatilis than in L. planeri. Since a similar more rapid change in L. fluviatilis has also been found in the switch from larval to adult haemoglobin, the former type of haemoglobins may be produced only in erythrocytes originating in the nephric fold and typhlosole, whereas the latter type may be restricted to cells developed in the fat column. It is also suggested that the functional significance of the alteration in haemopoietic sites is related to changes at metamorphosis in the three regions where blood cell formation occurs.
Allometry of the limbs of antelopes (Bovidae)*
Authors: Alexander R. McN.
Published: August 2009

The principal bones, muscles and tendons in the legs of seven species of antelope of varying size have been measured, and aliometric equations have been derived. Some data published by Sachs (1967) have also been analysed. Most of the exponents of the aliometric equations agree well with McMahon's (1973, 1975a) theory of elastic similarity: lengths are approximately proportional to (mass)0˙25, diameters to (mass)0˙375 and cross‐sectional areas to (mass)0˙75. However, some of the exponents for diameters and areas in the hind leg are significantly different from those predicted by the theory.

The results are discussed in conjunction with previously published data on fast galloping. It is shown that maximum stresses in bones, muscles and tendons are probably more or less independent of body mass in antelopes galloping at their maximum speed. The tensile stresses in the tibia and humerus approach the tensile yield strength of bone. The total work which is done by the muscles in each stride at maximum speed and the energy saved by elastic storage are probably more or less proportional to body mass. The deviations of some of the allometric exponents for diameter from the expected value of 0middot;375 are partially explained.
Growth of young vertebrates in the egg or uterus
Authors: Frazer J. F. D.
Published: August 2009

In eutherian mammals, foetal growth shows a straight‐line relationship between time and cube root of foetal weight. The same relationship has now been found to hold for the embryos in birds' eggs and is postulated for reptiles. In marsupials the specific foetal growth rate does not exceed that already known for the higher primates. Outside the eutherian mammals, only the birds have developed high embryonic growth rates, but in exchange for other disadvantages.
Determinants of avian eggshell porosity
Authors: Tullett S. G. , Board R. G.
Published: August 2009

The manner in which the porosity of avian eggshells varies with egg weight is discussed in relation to the number of pores, their cross‐sectional area and length. Shell porosity and ways in which this can change to satisfy different environmental demands are discussed on the basis of a simple model which envisages the shell as being composed of columns of calcite.
The behaviour of chaetodontid fishes with special reference to Lorenz' “poster colouration” hypothesis*
Authors: Ehrlich P. R. , Talbot F. H. , Russell B. C. , Anderson G. R. V.
Published: August 2009

Behaviour of chaetodontid fishes relevant to Lorenz's “poster colouration” hypothesis has been studied. Field observations of 20 species at Lizard Island, Great Barrier Reef, showed that these chaetodontids rove over large areas of reef, occurring singly or in pairs and sometimes sizeable groups. The behaviour of chaetodontids does not support the supposed explanation of poster colours as intra‐specific sign stimuli serving to space individuals. During daytime, agonistic encounters are rare, even amongst groups, and for most species there is no evidence of territoriality. Experiments presenting painted and blank chaetodontid models to eight species generally confirmed these observations. At dusk and dawn, chaetodontids are aggressive and defend regular night‐resting places. Agonistic encounters though, are both intra‐ and inter‐specific; they serve to space individuals over only very small distances, and colouration seems to have little warning value. The question of the functional significance of poster colours remains largely unsolved. Amongst chaetodontids, territoriality clearly is not a major function and the evidence suggests that other kinds of social communication, as well as predator avoidance, have probably been important in the evolution of poster colouration.
The use of shell features in age determination of juvenile and adult Roman snails Helix pomatia
Authors: Pollard E. , Cooke A. S. , Welch J. M.
Published: August 2009

Features of the shell which can be used for aging Roman snails Helix pomatia L. are described. Field evidence suggests that growth breaks in the shell correspond to resting periods during the winter in the juvenile phase of shell growth. The microstructure of the shell is described and the structure of the juvenile breaks and layering in the lip of the adult snail are shown to be similar. It is concluded that the two are analogous, that the layers at the lip are annual, and that it is theoretically possible to trace the adult shell back to the year of hatching. In practice, errors may be made in recording, but the method can be of great value in population studies.
Seasonal changes in the prepuce of adult Fallow deer (Dama dama) and its probable function as a scent organ
Authors: Kennaugh* J. H. , Chapman D. I. , Chapman** Norma G.
Published: August 2009

The penis sheath of adult Fallow deer, which is an integral part of the abdominal skin, extends from the scrotum to the preputial orifice. Marked seasonal changes occur in the prepuce. In the non‐rutting animal, the outer region of the prepuce, which is similar in structure to normal skin, passes through a transition zone characterized by a corrugated epidermis and multi‐lobed sebaceous glands, before becoming the inner‐sheath lining. Just before the rut, hypertrophy of the epidermis of the transition zone occurs with the formation of keratinous villi‐like processes. The sebaceous glands enlarge and lipid production is increased. At the beginning of the rut, the transition zone everts and becomes located on the outer periphery of the prepuce, which now has the appearance of a dark brown, coarse, short‐haired brush. At this stage, the animal and its voided urine develop a characteristic pungent odour whereas urine aspirated from the bladder is relatively odourless. After the rut, the prepuce returns to normal, the keratinous papillae being shed. It is suggested that the strong smelling rutting odour of male Fallow deer helps to synchronize oestrus in the females. The gross hyperkeratosis and associated epidermal hypertrophy of the prepuce produces a sponge‐like mass which may help in scent production and dispersal.
The influence of snow conditions on the date of breeding of wading birds in north‐east Greenland
Authors: Green G. H. , Greenwood J. J. D. , Lloyd C. S.
Published: August 2009

The young of wading birds that breed in some parts of the arctic hatch when their insect food supply is most abundant. This appears to be the ultimate factor determining the date of egg‐laying. In various other arctic birds the date of breeding may be influenced, directly or indirectly, by the time at which snow or ice melts. The Joint Biological Expedition to N.E. Greenland 1974 studied Ringed ploversCharadrius hiaticula, DunlinsCalidris aplina, SanderlingsCalidris alba, KnotsCalidris canutus, and TurnstonesArenaria interpresbreeding in various areas within 80 km of each other.

In 1974 the thaw was two or three weeks later than normal in the region. The time at which snow cleared and the dates of breeding of the waders differed considerably between valleys: breeding was delayed in valleys that cleared late. In all areas egg‐laying ceased early in July, probably because chicks hatching from eggs laid later would not be ready to migrate by the end of the summer. Hence the mean date and length of the egg‐laying period were determined by the date of snow clearance from the breeding areas.

Studies of the potential food resources indicate that the waders in N.E. Greenland do not appear to time their breeding so that the young hatch at some peak of food abundance. Sufficient food resources are probably available over a long period of time.
Arterial disease of reptiles
Authors: Finlayson R. , Woods S. J.
Published: August 2009

The pathological features of arterial lesions observed in a series of 200 exotic reptiles dying in captivity are described. Macroscopic disease was noted in 18% of the animals, and a further 11% showed microscopic arterial changes. Medial calcification, secondary to a parasitic arteritis or associated with nutritional bone disease, constituted the major vascular disorder. Lipid‐containing intimal lesions were both uncommon and of very limited extent; possible reasons for this low incidence are discussed.
The clypeal glands of Mynoglenes and of some other linyphiid spiders
Authors: Blest A. D. , Taylor H. H.
Published: August 2009

The clypeal glands of three New Zealand Linyphiidae currently placed in Mynoglenes are described, by light, scanning and transmission electron microscopy. Shallow sulci beneath the lateral eyes of both sexes trap secretions which are produced by greatly elongated cells packed radially with respect to a given sulcus, and each voiding its product to the exterior by an individual ductule. The function of the secretion is unknown, although the ultrastructure of the gland resembles that of the defensive glands of many insects, but there is no separate duct cell, and the basal region of each secretory cell exhibits a unique strategy of membrane amplification, which divides the cytoplasm longitudinally into compartments by folds of the plasma membrane, compartments being still further subdivided into “tails”. Patterns of vacuolation observed in various regions of the cytoplasm support the hypothesis that these unusual structures may be concerned with rapid water transport from the haemocoele, and that the cells discharge their contents by a “flush‐out” mechanism. It is shown that male Erigoninae with cephalic specializations have similar clypeal glands, but with cytological profiles (in alcohol‐fixed material) which suggest that special forms of membrane amplification are not present. Glands are absent in female Erigoninae, and in males with unmodified heads. It is suggested that in this latter subfamily the cephalic modifications may serve as presenting surfaces for sexual pheromones.