bluuebunny/crossref_metadata_2025 huggingface dataset:
Notes on Vampyrum spectrum, the false vampire bat, in Panama
Authors: Peterson R. L. , Kirmse Peter
Published: August 2008

A specimen of the carnivorous bat, Vampyrum spectrum, taken at Cerro Punta, Province of Chiriqui, Panama, on March 14, 1968, appears to represent the first record of this species preying on other bats caught in mist nets. Bat and rodent remains, as well as pieces of mist net, were recovered from the intestinal tract. Less than a dozen specimens of this species have been reported from Panama, all from much lower elevations. Measurements are given which provide further evidence that the species is monotypic.
On the structure and enzymatic degradation of the external membrane of the salmon egg
Authors: Bell Gordon R. , Hoskins Gary E. , Bagshaw John W.
Published: August 2008

The radiate membrane ("capsule") of chum salmon (Oncorhynchus keta) eggs has integrated with it another, outermost, non-chitinous membrane which prevents the digestion of the radiate membrane by "hatching enzyme" of chum salmon or by pronase applied externally but not internally. Crude chum salmon hatching enzyme(s) has an optimum pH of 7.5–8.0 for the release of soluble peptides from the radiate membrane, requires metal ions for activity, and can also decompose the radiate membranes of coho salmon (Oncorhynchus kisutch) and steelhead (Salmo gairdneri) eggs.
"Elastic" fibers in the mesogloea of Pachycerianthus torreyi (Anthozoa)
Authors: Arai Mary Needler
Published: August 2008

The presence of "elastic" fibers in addition to collagen in the mesogloea of the column wall of Pachycerianthus has been demonstrated by staining with spirit blue or aldehyde – fuchsin after oxidation with potassium permanganate.
On the rotifer Keratella canadensis Berzins
Authors: George M. G. , Fernando C. H.
Published: August 2008

Keratella canadensis Berzins described from Canada is considered a form of Keratella quadrata Müller. Evidence for this comes from the appearance of this form in two lakes only once for 3 consecutive months during 2 years' regular sampling and the presence of typical "quadrata" characters. "Keratella canadensis" appears to have morphological features which place it at one extreme of the very variable Keratella quadrata.
Harvestmen and spiders and their prey on milkweed, Asclepias syriaca L., at London, Ontario
Authors: Judd W. W.
Published: August 2008

Harvestmen, Phalangium opilio, and spiders, Philodromus cespitum, Phidippus whitmani, and Dictyna foliacea, were found on flowers and leaves of milkweed. Dictyna foliacea was the commonest species and spun flat webs across the leaves and captured aphids, leafhoppers, plant bugs, and flies of several families as prey.
The effects of an acute DDT exposure on the spontaneous electrical activity of goldfish cerebellum
Authors: Aubin A. E. , Johansen P. H.
Published: August 2008

Goldfish exposed to 1.0 p.p.m. DDT in water for 2.5 hours show a complete loss of balance as well as an increase in the amplitude and a decrease in the frequency of the spontaneous electrical activity of the cerebellum. After 6 hours recovery in uncontaminated water they recover their balance and the cerebellar electrical activity returns to control levels.
Ecology of the American dog tick, Dermacentor variabilis (Say), in Nova Scotia
Authors: Dodds Donald G. , Martell Arthur M. , Yescott Richard E.
Published: August 2008

The American dog tick has been extending its range in western Nova Scotia since about 1940. The presence of a number of suitable hosts, a temperate, moist climate, and logging operations producing an interspersion of choice vegetative conditions allow relatively high densities and a continuous spread. Seven small mammal species act as hosts. The most important hosts of immature stages are meadow vole (Microtus pennsylvanicus), deer mouse (Peromyscus maniculatus), southern bog lemming (Synaptomys cooperi), and meadow jumping mouse (Zapus hudsonius). Important hosts for adult stages are porcupine (Erethizon dorsatum), raccoon (Procyon lotor), and black bear (Ursus americanus).
A new technique for the collection of urine of small fishes and for the study of exchanges of materials via the head region
Authors: Lam T. J.
Published: August 2008

A technique is described for the collection of urine of small fishes, such as the threespine stickleback, Gasterosteus aculeatus L., form trachurus, and for the study of exchanges of materials via the head region. It involves suspension of the fish by a rubber diaphragm just posterior to the opercula, with the head region in continuously oxygenated water and the remaining body in paraffin oil. Urine collects as drop(s) in the paraffin oil. The limitations and advantages of the technique are discussed.
The biology of Gammarus (Crustacea, Amphipoda) in the northwestern Atlantic. I. Gammarus duebeni Lillj.
Authors: Steele D. H. , Steele V. J.
Published: August 2008

Gammarus duebeni is found as far north as southern Labrador and northern Newfoundland in brackish water habitats, but is absent from fresh water in the northwest Atlantic region. A population at Holyrood, Newfoundland, has been studied from 1962 to 1968. Fifty percent maturity for the females occurs at 11.5 mm in the winter and 10.5 mm in the summer. Embryos increase in size with development but at the same stage are significantly larger in the winter than in the summer. Mature females produce a succession of broods between November and August, at which time they enter the resting stage. The November brood develops slowly at the prevailing winter temperature and the young are released the next March. Fecundity increases with size of female. The winter broods are reduced in size with development which is not true of those produced in the summer. Females have a higher mortality rate than males and survive at the most for 1 year. The males are larger and live longer.
Histogenesis of the rostellum of Taenia crassiceps (Zeder, 1800) (Cestoda), with special reference to hook development
Authors: Bilqees Fatima Mujib , Freeman Reino S.
Published: August 2008

Histogenesis of the rostellum of Taenia crassiceps is described. The syncytial tegument and various cells take an active part in this differentiation. The increase in number of these cells as well as nuclei associated with the tegument, and changes in their relationship with one another, dominate the process. A specialized portion of the tegument termed the "hook organ" and its function in rostellar hook formation is considered. Rostellar hooks are produced de novo and not from fused microtriches as stated by some. When the hook organ is most active it is not separated from the underlying tissues by the subtegumental circular and longitudinal muscle layer as is the tegument of the adjacent bladder wall. When the rostellar hooks are fully differentiated the hook organ becomes an inner and outer ring of receptacles each with its own hook.
Hepatoxylon trichiuri (Holden 1802) (Cestoda—Trypanorhyncha) from the giant squid Architeuthis dux Steenstrup 1857 in Newfoundland
Authors: Pippy John H. C. , Aldrich Frederick A.
Published: August 2008

A postlarva of the trypanorhynch, Hepatoxylon trichiuri (Holden 1802), was discovered in the caecum of the giant squid, Architeuthis dux Steenstrup 1857. This may establish a selachian or a teleost as being food of the architeuthid, about which subject there is no direct information.
New definitive host, range extension, and notes on the morphology of Tristriata anatis Belopolskaia, 1953 (Trematoda, Notocotylidae) from southeast Alaska
Authors: Frame George W.
Published: August 2008

Two surf scoters (Melanitta perspicillata L.) from near Juneau, Alaska, were examined; a total of 22 Tristriata anatis Belopolskaia, 1953, were removed from the ceca and large intestine. This is the second reported discovery of T. anatis, the first in North America, and a new host record. The species description is expanded. Morphology and the influence of methods on interpretation of structures are discussed.
Regulation of external respiration by the book-lung spiracles of the spiders, Araneus diadematus Clerck and A. marmoreus Clerck
Authors: Robinson G. L. , Paim U.
Published: August 2008

Recordings were made of the movements of the valves of the book-lung spiracles of Araneus diadematus Clerck and A. marmoreus Clerck. The slit-like spiracles of quiescent spiders were usually almost closed, but opened widely whenever the spiders moved. Respirometry indicated that CO2, retained in the spiders while the spiracles were closed, was released in bursts when the spiracles opened. High ambient concentrations of CO2 as well as lack of O2 caused spiracular opening and continuous release of CO2 from the spiders. It is suggested that CO2 elicits, whereas O2 inhibits, spiracular opening.
Observations on the biology of Ergasilus spp. (Cyclopoidea: Copepoda) infesting North American freshwater fishes
Authors: Tedla Shibru , Fernando C. H.
Published: August 2008

The gills of 118 yellow perch, Perca flavescens; 18 pumpkinseed, Lepomis gibbosus; 14 rock bass, Ambloplites rupestris; and 15 smallmouth bass, Micropterus dolomieui, were examined for Ergasilus spp. Ergasilus caeruleus was recovered for pumpkinseed and E. confusus from yellow perch. Rock bass and smallmouth bass were infested with E. centrarchidarum and one immature specimen of this species was recovered from a pumpkinseed. The host preference of each parasite species is discussed. A relationship between the egg number of copepods with more than one host and the degree of host preference is suggested.
Nematode parasites of mammals (Dermoptera, Primates, Pholidota, Rodentia, Carnivora, and Artiodactyla) from North Borneo (Malaysia)
Authors: Myers Betty June , Kuntz Robert E.
Published: August 2008

The present report is one of a series concerned with the helminths of vertebrates taken by the U.S. Naval Medical Research Unit No. 2 Expedition to North Borneo in 1960. Nematodes were obtained from flying lemurs, primates, anteaters, rodents, carnivores, and hoofed mammals.
Physiological correlations of population density in the eastern chipmunk (Tamias striatus) and the white-footed mouse (Peromyscus leucopus)
Authors: Clulow F. V. , DesMarais A. , Vaillancourt J.
Published: August 2008

Populations of various densities of eastern, chipmunks (Tamias striatus lysteri (Richardson) and white-footed mice (Peromyscus leucopus noveboracensis (Fischer) were formed by the introduction of wild-trapped animals onto islands of different size on Heney (Little Whitefish) Lake, Quebec.The animals were subsequently recaptured and various indicators of adrenocortical activity, including levels of circulating eosinophils and plasma corticostcroids, were measured. The evidence indicated that activation of the adrenal cortex is directly correlated with population density in T. striatus but not in P. leucopus.The conclusions are discussed in relation to current theories on the regulation of mammalian population including J. J. Christian's hypothetical behavioural–physiological control mechanism.
The neurophysiology of respiration in decapod crustacea. II. The sensory system
Authors: Pasztor Valerie M.
Published: August 2008

The mechanoreceptors of the respiratory appendage were studied by histological and electrophysiological techniques.A new type of mechanoreceptor is described and named the "oval organ". It consists of a specialized oval patch of cuticle 1–2 mm in length which is traversed by a spine or longitudinal thickening. Closely applied to the cuticle is a pad of connective tissue richly supplied with dendrites from two large nerve fibers. The orientation of the spine and the dendrites ensures that the receptor responds preferentially to certain stresses or foldings of the oval organ. It lies at the base of the scaphognathite on the dorsal surface.No internal proprioceptors were observed. Movements of the appendage are signalled either by the oval organ, epidermal receptors, or hair sensilla.The possible effect of sensory input upon the central respiratory rhythm generator is discussed.
First Newfoundland record of Peromyscus
Authors: Gould Walter P. , Pruitt Jr. William O.
Published: August 2008

A single specimen of Peromyscus maniculatus is reported from the island of Newfoundland.
Plicobothrium globicephalae gen. et sp. nov. (Cestoda:Diphyllobothriidae) from the pilot whale, Globicephala melaena Traill, in Newfoundland waters
Authors: Rausch R. L. , Margolis L.
Published: August 2008

Plicobothrium globicephalae gen. et sp. nov., described from the pilot whale, Globicephala melaena Traill, from Trinity Bay, Newfoundland (eastern Canada), is distinguished by complex folding of the modified bothria of the scolex in combination with other morphological characteristics. Of diphyllobothriid cestodes occurring in marine mammals, those of the monotypic genera Pyramicocephalus Monticelli, 1890, and Baylisiella Markowski, 1952, have modified scolices, but of a different type. P. globicephalae gen. et sp. nov. is further distinguished from these by characteristics of the strobila, arrangement of excretory ducts, and other morphological differences. The taxonomic status of other diphyllobothriid cestodes in marine mammals is briefly discussed.
Two new species of the spider genus Schizocosa (Araneida: Lycosidae) from the Great Lakes region
Authors: Dondale C. D.
Published: August 2008

Two new species of Schizocosa are described and illustrated, namely, S. heasmani from meadow habitats in eastern Ontario and S. aulonia from the beaches and sand dunes of northeastern Illinois. These species closely resemble, respectively, S. avida (Walckenaer) and S. retrorsa (Banks), which are also illustrated.
Variations in the plasma proteins of Atlantic salmon (Salmo salar L.)
Authors: McKenzie J. A. , Paim U.
Published: August 2008

The plasma proteins of 51 juvenile Atlantic salmon were examined by vertical acrylamide gel electrophoresis. Eight distinct phenotypes were found from specimens originating from a single river system in New Brunswick. The potential use of these polymorphisms for identifying populations is discussed.
Changes in some haemolymph dehydrogenase isozymes of the female honeybee, Apis millifera L., during caste development
Authors: Tripathi R. K. , Dixon S. E.
Published: August 2008

The electrophoretic distributions of six dehydrogenases are described for the two female castes of honeybee larvae. Pronounced differences with time within a caste and between castes were noted. Worker larval haemolymph showed a greater number of isozymes for all dehydrogenases studied except glyceraldehyde-3-phosphate.Spectrophotometric assays of three of the dehydrogenases gave quantitative expression to electrophoretic results. Haemolymph from worker larvae generally showed maximum activity earlier than that from queen larvae. Enzyme activity showed a general decline in both castes during the later stages of larval life. The activity of glucose-6-phosphate and 6-phosphogluconate dehydrogenases suggest that the pentose phosphate pathway of glucose metabolism is important during larval life.
Effects of methyl testosterone on the testis and secondary sex characters of the hypophysectomized adult guppy Poecilia reticulata Peters
Authors: Pandey S.
Published: August 2008

Exogenous methyl testosterone appears to have a direct spermatokinetic effect on the testis of the hypophysectomized adult guppy. The gonosomatic index is significantly increased; spermatogonial cysts divide rapidly and transform into spermatocytes, but later stages of spermatogenesis do not appear. The regressed epithelial cells lining the sperm ducts, the Sertoli cells, and the interstitial cells resume their normal appearance. The gonopodium remains unaffected, but there is moderate recovery in the content of integumentary lipophores.
Incidence and abundance of certain parasites in wapiti in the national parks of the Canadian Rockies
Authors: Flook D. R. , Stenton J. E.
Published: August 2008

One hundred and seven wapiti Cervus canadensis, collected at different seasons of the year in Banff and Kootenay Parks, and the Ya Ha Tinda Ranch near Banff Park, were examined for helminth and arthropod parasites, Additional data were obtained by inspecting lungs and livers in 1380 wapiti shot in early winter for population control in Jasper, Banff, and Waterton Lakes National Parks. Species commonly found in some areas were Fascioloides magna, Thysanosoma actinoides, Echinococcus granulosus, Dictyocaulus viviparus, and Dermacentor albipictus. Incidence and abundance of these species are compared between wapiti of different sex and age. Seasonal and spatial distributions of parasites are also discussed.
Activité estivale de petits mammifères du Québec
Authors: Thibault Paul
Published: August 2008

not available
The cephalic and caudal musculature of the sculpin Myoxocephalus polyacanthocephalus (Pisces: Cottidae)
Authors: Cowan Garry I. McT.
Published: August 2008

The cephalic and caudal musculature of the sculpin Myoxocephalus polyacanthocephalus was investigated in an effort to determine whether the rather radical modification of the body form and mode of life of many of the cottids from that of the more typical perciform fishes was in any way reflected by the musculature.The differences encountered in the cephalic musculature proved to be mainly ones of degree of development, the only major one being the extreme development of the levator arcus palatini, the muscle primarily responsible for the erection of the preoperculum, the primary defense mechanism of cottids.Comparison of the caudal musculature revealed the absence of a deltoit flexor tendon and also of a dorsal adductor muscle.
The haematocrit centrifuge for the detection of trypanosomes in blood
Authors: Woo Patrick T. K.
Published: August 2008

A capillary tube holder, devised to minimize shadow effects during microscopic examination of haematocrit capillary tubes for trypanosomes, is described. A blood dispenser, designed to remove trypanosomes from centrifuged tubes, resulted in thinner smears of trypanosomes covering a smaller area. The anterior end of centrifuged trypanosomes was abnormally thickened and the kinetoplast displaced posteriorly.
Monogenetic trematodes from Newfoundland, Canada. 1. New species of the genus Gyrodactylus Nordmann, 1832
Authors: Hanek George , Threlfall William
Published: August 2008

Five new species of Gyrodactylus, namely Gyrodactylus avalonia, G. canadensis, G. lairdi, G. memorialis, and G. terranovae, are described and figured from Gasterosteus aculeatus Linnaeus, 1758 and Gasterosteus wheatlandi Putnam, 1867 caught in Newfoundland, Canada. This is the first record of a species of Gyrodactylus being recovered from G. wheatlandi.
Development of rostellar hooks in Paricterotaenia paradoxa (Cestoda:Cyclophyllidea)
Authors: Scott J. S.
Published: August 2008

Changes in the distribution and form of the hooks during development of larval Paricterotaenia paradoxa are described. The distribution changes from a rostellum covered with small hooks to a double crown and, finally, to a single crown of definitive hooks. These changes may be of phylogenetic significance.
Feeding of the least, crested, and parakeet auklets around St. Lawrence Island, Alaska
Authors: Bédard Jean
Published: August 2008

The feeding habits of three plankton-feeding Alcidae, the least, crested, and parakeet auklets were studied on St. Lawrence Island, Alaska, between 1964 and 1966. The crested and the least auklets (Aethia cristatella, A. pusilla) exhibit similar patterns of dependence upon the food resources: both have, during early summer, a diversified diet consisting of mysids, hyperiids, gammarids, etc., but restrict themselves largely to one principal prey during the chick-rearing period. Then, A. pusilla eats mostly Calanus sp. while A. cristatella eats Thysanoessa spp. In all years, hatching coincided closely with the appearance of these prey items (copepods and euphausids) in the environment and it is argued that the timing of the auklets' breeding season has been adjusted to their cyclical abundance. Cyclorrhynchus psittacula, the parakeet auklet, maintains a diversified diet throughout the summer: Parathemisto libellula, a pelagic amphipod, is the dominant prey in its diet.The three species are found feeding together and are presumed to use the same depth range. Segregation in feeding between A. cristatella and A. pusilla is achieved by difference in bill size. This difference is sufficient to impose obligatory feeding upon different resources. Segregation between two possible competitors, A. cristatella and Cyclorrhynchus, seems to rest upon innate preferences for different prey types, minor structural differences in the feeding apparatus, and differences in foraging habits: the relative importance of each of these factors remains to be established.As a whole, the amount of overlap in feeding between the three species studied is very small.
Transferrin polymorphism among populations of the arctic ground squirrel, Spermophilus undulatus (Pallas)
Authors: Nadler Charles F. , Youngman Phillip M.
Published: August 2008

Starch-gel electrophoresis of sera from Canadian and Alaskan populations of Spermophilus undulatus demonstrates four molecular trausferrins, Tf 5, 6, 7, and 8. Single and double band transferrin patterns reflect homozygous and heterozygous genetic expression respectively.Spermophilus undulatus parryii is characterized by Tf 6 alone or in combination with Tf 7 or Tf 8, S. u. ablusus by Tf 7 alone, and S. u. plesius by Tf 5 alone or in combination with Tf 7.Transferrins offer a means for clarifying the taxonomy of this holarctic species complex, and for investigating the origins and distributions of nearctic populations.
Initiation of breeding behavior in the American toad, Bufo americanus
Authors: Oldham R. S.
Published: August 2008

Breeding behavior in Bufo americanus, which is a predominantly terrestrial anuran, was studied in two closely associated groups of pools. It was initiated at different dates in these and may have been induced by differences in air temperature which differed by as much as [Formula: see text].
Digenetic trematodes from Newfoundland, Canada. 2. Two species from Gasterosteus aculeatus Linnaeus, 1758
Authors: Hanek George , Threlfall William
Published: August 2008

Crepidostomum cooperi Hopkins, 1931 and Derogenes varicus (Mueller, 1784) are recorded for the first time from Newfoundland. The threespine stickleback is a new host for both parasites.
Moose (Alces alces) milk. Gross composition, fatty acid, and mineral constitution
Authors: Cook H. W. , Rausch R. A. , Baker B. E.
Published: August 2008

Milk was collected from three moose which were killed near Fairbanks, Alaska. The gross composition and the fatty acid and the mineral constitution of the moose milk were determined.
The rate of thermal exchange in a teleost, Tilapia mossambica
Authors: Stevens E. Don , Fry F. E. J.
Published: August 2008

Excess tissue temperatures of a fish in a stable thermal environment were estimated. In fish weighing 40 to 200 g, mean excess muscle temperature was 0.44 °C and brain, 0.45 °C. A significant high local excess temperature (0.80 °C) was observed in the isthmus, immediately under the skin just anterior to the pelvic girdle. Mean excess muscle temperature in fish weighing less than 40 g was 0.15 °C.The rate of thermal exchange of fish was estimated by measuring the tissue temperature after the fish was placed m a bath 5 °C cooler than ambient. The slope of a double logarithmic plot of the coefficient of cooling versus body weight was −0.3. The coefficient was 1.8 °C/min per °C difference for fish weighing 1.0 g and was 0.4 for fish weighing 100 g.
Freshwater ostracodes of Canada. Part II. Subfamily Cypridopsinae and Herpetocypridinae, and family Cyclocyprididae
Authors: Delorme L. D.
Published: August 2008

The subfamily Cypridopsinae is represented in Canada by seven species belonging to the two genera Cypridopsis and Potamocypris; the subfamily Herpetocypridinae is represented by three species belonging to the two genera Herpetocypris and Prionocypris; the family Cyclocyprididae is represented by 10 species belonging to the three genera Cyclocypris, Cypria, and Physocypria.
The feed intake and heat production of the young black-tailed deer (Odocoileus hemionus columbianus)
Authors: Nordan H. C. , Cowan I. McT. , Wood A. J.
Published: August 2008

The feed intake, resting heat production, and growth rate of prepubertal black-tailed deer fawns of both sexes have been studied under captive conditions. Comparisons of these findings with those of other workers on domestic and other wild species are presented. The present results provide some explanation for the unusual growth behavior of this species when reared on a high plane of nutrition.
Hormonal control of spermatogenesis in the cockroach, Periplaneta americana (L.)
Authors: Blaine W. D. , Dixon S. E.
Published: August 2008

A surgical approach was made to the question of humoral regulation of testicular development. Neither the neurosecretory cells nor the prothoracic glands retarded or accelerated development of the testes. The corpora allata maintained the testes in a juvenile state by retarding their development.
Further observations on the food and predatory habits of the gray jay
Authors: Ouellet Henri
Published: August 2008

The gray jay (Perisoreus canadensis) has been observed feeding on a variety of items ranging from several types of animal carcasses to axle grease and dried fruits. Other observations pertain to its predation on nests and young of several species of birds and on certain small mammals in the coniferous forest. It is suggested that this bird may be an important predator and scavenger, the rôle of which is still mostly undetermined.
The fine structure of Leucocytozoon simondi. I. Gametocytogenesis
Authors: Desser Sherwin S. , Baker John R. , Lake Pamela
Published: August 2008

Merozoites from hepatic and megaloschizonts are bounded by a single membrane and are slightly irregular in shape. They possess a single nucleus and mitochondrion, and electron-dense paired organelles associated with a polar ring. Hepatic merozoites develop in polychromatic and mature erythrocytes to form round gametocytes. Those from megaloschizonts develop in white cells, primarily lymphocytes, to form elongate gametocytes. Unlike hepatic merozoites the sex of the megalomerozoites can be recognized while they are still within the schizont. The cytoplasm of female merozoites, like that of mature gametocytes, is considerably darker than that of the male because of the density of ribosomes in the former. Mature macrogametocytes contain a compact nucleus, accumulations of dense material, mitochondria, lipid inclusions, and small electron-dense bodies. Microgametocytes have a lighter cytoplasm containing a large nucleus bounded by a double membrane with invaginations in which mitochondria are found. Mature gametocytes are bounded by an 11-layered pellicle. Endogenous bands of microtubules were observed in elongate gametocytes but not in the round forms. Feeding appears to be restricted to diffusion in immature gametocytes and to pinocytotic uptake of host cytoplasm in maturing forms. The peculiar dimorphism of gametocytes and their possible significance in the life cycle are discussed.
The structure and function of the digestive system during postembryonic development in Lytta nuttalli Say (Coleoptera: Meloidae)
Authors: Morgan Anne , Church N. S. , Rempel J. G.
Published: August 2008

The digestive tract of Lytta nuttalli goes through three structural phases, correlated with the insect's trophic phases. The wholly or partly carnivorous larvae have an almost straight tract with a relatively short stomodaeum and proctodaeum, while the phytophagous adult has a convoluted system with a long fore- and hind-gut. In the two intervening non-feeding larval instars the tract is greatly reduced. Changes in the structure and histology of each part of the system, including changes in the apparent activity of the midgut epithelium, are described and related to the changes in diet and feeding habits. The foregut of the adult has a complex armature and probably functions as a triturating mechanism. In each stage there apparently is only one mature midgut epithelial cell type. A brush border composed of microvilli is present in the feeding stages. Regenerative cells are located in basal nests in the feeding larvae, protruding crypts in the adult, and isolated clusters in the non-feeding larvae. A peritrophic membrane of dual origin is present in the feeding stages; it is thin and continuous in the larvae, thick and fragmented in the adult. The colon, with its associated cryptonephridial system, appears to be the main site of water absorption; it is especially well developed in the adult.
The association of Calliactis tricolor with its pagurid, calappid, and majid partners in the Caribbean
Authors: Cutress C. , Ross D. M. , Sutton L.
Published: August 2008

Calliactis tricolor (Lesucur) lives most commonly in Puerto Rico as a commensal on Turbo and Fasciolaria shells, and less commonly on Murex shells inhabited by the pagurid Dardanus venosus. The partnership is less dependent on the response of the anemone to the shell than the European partnership between C. parasitica and D. arrosor. Besides D. venosus, which is active towards C. tricolor, another larger pagurid, Petrochirus diogenes, and the spider crab Stenocionops furcata display extremely effective behavior patterns in transferring the anemone. S. furcata may carry as many as 20 to 30 C. tricolor on its carapace and legs. When it encounters C. tricolor attached to another surface, S. furcata uses chelipeds and walking legs in stroking, scratching, and pinching movements, at first gently, then more actively, until the anemone is freed. After a period of manipulation, the crab seizes the anemone firmly in one cheliped and hoists it overhead to place it on the carapace. Both chelipeds usually test the carapace beforehand for free areas. C. tricolor relaxes completely when stimulated and manipulated in these various ways, apparently in a state of general inhibition. A calappid crab, Hepatus epheliticus, on which C. tricolor lives in the Gulf of Mexico, occasionally showed rearing and rubbing of carapace on the tentacles in response to C. tricolor. This led the anemone to transfer to the crab. C. tricolor also transferred to H. epheliticus without such activity by the crab. In discussing the results, the authors emphasized the variety of tactile stimuli used by different crabs. This is reflected in a flexible response pattern in the anemone. The behavioral capacities of S. furcata, in responding to C. tricolor and in placing it on the carapace, are thought to be remarkable for a crustacean.
Effect of fasting and exercise on lipid levels in muscle. A cytological and biochemical study
Authors: Vallyathan N. V. , Grinyer I. , George J. C.
Published: August 2008

Light and electron microscopic studies on the effect of fasting and exercise on lipids in the pectoralis muscle of the pigeon have revealed considerable increase in intracellular as well as extracellular lipids (1) in fasted pigeons and (2) in normal and fasted pigeons when the muscle of one side was electrically stimulated for different periods of time. Similar increase in lipids was also seen in the contralateral quiescent muscle. These observations were confirmed by bioehemical assays of the lipid content in the muscle under identical experimental conditions. It is concluded that the intracellular muscle lipids are not immediately drawn upon for energy either during exercise or fasting as long as there is ready supply of lipids transported through the blood stream from external sources such as adipose tissue.It was also observed that the inflow of lipids into the muscle was to, the fat-utilizing red fibers and not the glycogen-utilizing white fibers, which, even normally, contain no- intracellular lipid inclusions. The intracellular transport of lipids in muscle, therefore, may be considered a selective process. The mitochondria of both types of fiber in the exercised muscle appeared to be swollen.
A method for studying spiders at various stages of development
Authors: Seligy V. L.
Published: August 2008

An apparatus has been described for obtaining microscope observations, linear measurements, or photographs of live immature or mature spiders without any apparent damage to the individuals.
Electron microscopic study of the mantle of normal and regenerating Helix
Authors: Saleuddin A. S. M.
Published: August 2008

Histology of the mantle of normal Helix pomatia has been studied both by light and electron microscopes, and changes that occur in the general outer mantle epithelium during shell regeneration have been recorded. Mantle edge can be subdivided into three zones, (a) glandular epithelium (b) periostracal gland, (c) general outer epithelium. Ephithelial cells lining each of these three zones have a characteristic structure. Cells of the glandular zone have two types of inclusions: (1) near the secretory surface, which are nearly empty looking and oval; (2) mostly round and present in the basal region of the cells showing characteristic patterns. Underneath the glandular epithelium are five types of gland cells. Cells of the periostracal gland contain secretory droplets, most of which are homogenous, while others contain closely apposed membranes. It is suggested that these glands be called "shell glands" instead of "periostracal glands" because of the absence of direct evidence that they elaborate periostracum. Outer epithelial cells have lamellar organelles of 0,4 μ to 0.8 μ, in diameter, many glycogen granules, fibrous structures, and secretory droplets. These droplets are different from those in the periostracal glands in that they are not delimited by a membrane.Situated in the thickness of the mantle are the Leydig cells and cells containing droplets showing different patterns.During shell regeneration, several changes in the outer mantle epithelium can be noticed, including an initial increase of the lamellar organelles followed by a decrease and eventual loss of these organelles. Mitochondria increased in number. Lamellar organelles are either transformed mitochondria or formed from multivesicular bodies.
The fine structure of Leucocytozoon simondi. II. Megaloschizogony
Authors: Desser Sherwin S.
Published: August 2008

Incompletely divided cytomeres released from hepatic schizonts of L. simondi undergo prolific development in phagocytic cells of the host which become grossly hypertrophied. These infected cells together with the parasites within are termed megaloschizonts. Young megaloschizonts contain numerous round cytomeres bounded by a five-layered envelope. With further development the cytomeres expand and become invaginated. Microtubular spindles occur in dividing parasite nuclei at this stage of development. Thickenings form on the single membrane bounding the newly formed cytomeric surfaces. Electron-dense paired organelles develop adjacent to the thickenings which become the polar rings of merozoites. Abundant granular endoplasmic reticulum and numerous mitochondria with vesicular cristae are seen in the cytoplasm of invaginated cytomeres. Nuclear division by multiple fission and further cytoplasmic fragmentation continue until uninucleate merozoites are formed. Male and female merozoites can be distinguished by the difference in the density of their cytoplasm and each contains a mitochondrion and paired organelles with the associated polar ring. The megaloschizont is surrounded by a capsule whose irregular inner surface is lined by the host plasma membrane. Outside this lies a thick filamentous zone from which numerous vesicles are pinched off and are seen within the hypertrophied host cytoplasm. A fibrous layer bounds the outer surface of the megaloschizonts.
Encephalization in Chiroptera
Authors: Pirlot Paul , Stephan Heinz
Published: August 2008

The brain weights of 51 species of Chiroptera belonging to 10 families were compared using the allometry formula and based on the brain weights of some of the most primitive recent Insectivores. Estimates for the degree of encephalization of the various systematic and dietary groups of bats were given in the form of progression indices. A certain amount of between-group overlap was observed.The lowest encephalized group is formed by the Emballonuridae, Molossidae, Vespertilionidae, Rhinolophidae, and Hipposideridae; a median position is occupied by the Nycteridae and Phyllostomatidae; and the highest position by the Desmodontidae and Pteropidae. The Noctilionidae are present in the lowest as well as in the highest groups in relation to differences in feeding habits of the various species. The following ascending order of encephalization was found: insect-eating forms, nectar feeders, frugivorous Microchiroptera, piscivorous species, bloodsuckers, and frugivorous Megachiroptera.The encephalization indices for the Chiroptera do not exceed the upper limit attained by progressive Insectivores while they reach to some extent into the lowest zone of the Prosimians.Before one can ascertain the true nature of the relationship between systematic and dietary groups and encephalization, a detailed investigation of the brain structures in various species must be carried out; this is now being done.
Scanning electron microscopy of the spines of the tunic of the ascidian, Boltenia ovifera
Authors: Mishra A. K. , Colvin J. Ross
Published: August 2008

The presence of small spines on the exterior surface of the tunic of Boltenia ovifera, which contain axially oriented microfibrils of cellulose, was confirmed by scanning electron microscopy. These spines axe a continuous extension of the mass of the tissue without a recognizable discontinuity between them and the rest of the tunic. They show a trilobed form at their base after preparation for electron microscopy but this may be a result of desiccation. Tips of the spines are blunt and they, as well as the axial microfibrils which compose the shaft, are enclosed in a sheath which seems to be amorphous. On the surface of the tunic, the water-insoluble glycoprotein component is sparsely distributed. The distribution and morphology of these spines pose unusual problems for the mechanism of extracellular synthesis and deposition of cellulose microfibrils.
Sex ratio of the American eel (Anguilla rostrata (LeSueur)) in Newfoundland waters
Authors: Gray R. W. , Andrews C. W.
Published: August 2008

The sex ratio of the American eel in Newfoundland was estimated from studies of 354 examples from two brackish water and three freshwater habitats in Newfoundland. Sections of each gonad were cut at 10 μ, stained with haematoxylin, and counterstained with eosin. The material was divided into four classes; namely, females, immature females, males, and undifferentiated eels. Females were found in both brackish water and freshwater areas, while only one male was present in the material.The state of maturity of silver eels leaving Topsail Pond in the fall was determined from ova diameters. Ova diameters ranged from 0.109 to 0.214 mm; the average was 0.165 mm. These results agree closely with those reported by Svärdson for migrating silver eels in Europe.
The internal morphology and histology of adult Caloglyphus mycophagus (Mégnin) (Acarina: Acaridae)
Authors: Kuo J. S. , Nesbitt H. H. J.
Published: August 2008

The internal morphology and histology of the adult Caloglyphus mycophagus is described from serial sections fixed in 10% acrolein and embedded in glycol methacrylate. The alimentary tract has a typical acarid form, characterized by a well-developed stomach bearing a pair of caeca, a distinct colon and rectum. A pair each of Malpighian tubules and salivary glands also are present. At least three types of cells are recognized in the wall of the stomach and caeca. The central nervous system comprises fused supra- and sub-oesophageal and ventral ganglia. The male reproductive system is characterized by the presence of asymmetrical testes and a single large median accessory gland; the gonads in the female are paired and symmetrical and a pair of accessory glands are present. Details of 11 pairs of body-wall muscles, 7 pairs of genital muscles, 3 pairs of excretory pore muscles, and a number of coxal, leg, and gnathsomal muscles are given. No tracheae nor spiracles were found, but one pair of oil glands is described. The thin cuticle consists of three layers. Attention is drawn to the anatomical differences between this species and other species and their functional significance is discussed.
Diplolaimelloides bruciei n. sp. (Monhysteridae: Nematoda), prevalent in marsh grass, Spartina alterniflora Loisel.
Authors: Hopper B. E.
Published: August 2008

Diplolaimelloides bruciei n. sp. is unique among the short-tailed species in the genus in having four pairs of genital papillae in the caudal alae instead of three and in having a much longer gubernaculum, i.e., 23–28 μ vs. 7–11 μ. The species is prevalent in submerged portions of the marsh grass Spartina alterniflora Loisel. in Barataria Bay, Louisiana.
Interaction between barren-ground caribou and muskrats
Authors: Kelsall John P.
Published: August 2008

Barren-ground caribou, Rangifer tarandus groenlandicus, have been observed to systematically expose, trample, and eat the pushups constructed on ice in winter by muskrats, Ondatra zibethicus, for feeding. Muskrats may be inconvenienced, or frozen out, by this behavior and the caribou may be attracted by the frozen but green vegetation of which the pushups are constructed.
Intranuclear elements in the Leydig cell of the snail Helix
Authors: Saleuddin A. S. M.
Published: August 2008

The presence of glycogen granules and a paracrystalline structure has been reported in the nucleus of the Leydig cell of Helix.
Specific inhibition of morphogenesis in Trichinella spiralis by insect juvenile hormone mimics
Authors: Shanta C. S. , Meerovitch E.
Published: August 2008

Farnesol and farnesyl methyl ether at concentrations of 10−3 and 10−4 M and linolenic acid (used as control compound) at a concentration of 10−3 M in the culture medium significantly inhibited the molting of Trichinella spiralis larvae in vitro. Moreover, farnesol at 10−3 to 10−4 M, farnesyl methyl ether at 10−3 to 10−5 M, and linolenic acid at 10−3 M inhibited the development of the larvae so that they remained coiled. These effects are regarded as non-specific and not related to the juvenile hormone activity of the test compounds. However, the inhibition of development of male copulatory appendages among those larvae that molted, by farnesol at 10−3 and 10−4 M and by farnesyl methyl ether at 10−6 and 10−7 M, is considered to be specific inhibition of morphogenesis attributable to the juvenilizing effects of these compounds. Two possible interpretations of the observed effect are presented.
Sexuality in the rock-boring clam Penitella penita (Conrad 1837)
Authors: Evans John W.
Published: August 2008

Penitella penita (Conrad) is a dioecious and oviparous clam. It differs from most marine invertebrates in that its growth is determinate and full sexual maturity is postponed until cessation of growth.
Immunochemical characteristics of rat skeletal muscle myosin
Authors: Abandowttz H. M. , Basrur P. K.
Published: August 2008

The method of preparation of a highly purified antigen from rat skeletal muscle (myosin) and the procedure for preparing specific antisera have been described. The globulin fraction of the antisera was labeled to demonstrate selective staining of skeletal and cardiac muscles. The localization of apple-green fluorescence in muscle cells indicative of antigenic sites of myosin was obtained with chick and rat embryo muscle tissue. The data presented indicate that cardiac and skeletal muscle myosin cross-react and that the antigenicity of myosin is not species-specific.
The effects of endrin on Microtus and Peromyscus. I. Unenclosed field populations
Authors: Morris Ralph D.
Published: August 2008

Effects of endrin on unenclosed field populations of Microtus pennsylvanicus and Peromyscus maniculatus were investigated from June 1966 to October 1968. Adjacent 7-ac control and experimental plots were live-trapped each summer at regular intervals before and after a single endrin application of 8.0 oz per acre to the experimental plot.Immediate and significant postspray declines in Microtus numbers occurred on the experimental plot but no long-term toxicological effect was demonstrated. The experimental Microtus population rapidly recovered in numbers, eventually exceeded prespray numbers in 2 years, and exceeded corresponding control numbers in all 3 years. In 1966 and 1968, significantly more new Microtus were captured during postspray trapping on the experimental than on the control plot, and recruits survived significantly better than new individuals entering the more stable control population.It is suggested that reduction in numbers and the presumed decrease in intraspecific aggressive encounters disrupted the social structure to such an extent that normal regulation of numbers was no longer possible. The experimental Microtus population appears to have responded to endrin as it would to a local depopulation by removal trapping.Although Peromyscus were more abundant on the experimental than on the control plot before the first endrin application, their numbers were significantly reduced after spray in 1966 and never did recover. Recruitment by immigration or breeding did not occur and all individuals captured on the experimental plot in 1967 and 1968 remained there for only one trapping period. A long-term toxicological effect on Peromyscus was demonstrated, indicating a differential response of the two small mammal species to endrin.