bluuebunny/crossref_metadata_2025 huggingface dataset:
A histochemical study of the developing tibiotarsus in Malathion-treated chick embryos
Authors: Ho M. , Gibson M. A.
Published: August 2008

Chick embryos were exposed to a teratogenic dose of Malathion at 5 days of incubation. The treated tibiotarsi developed micromelia, an asymmetrical deposition of bone spicules, and sites of reduced matrix within the cartilage model. The major histochemical differences occurred in the areas of reduced cartilage matrix. These included a reduction in sulfated mucopolysaccharide and ribonucleic acid content and an increased glycogen storage. Calcification was more extensive in the treated tissues and premature centers of mineralization appeared within the epiphyses. Alkaline phosphatase was associated with sites of ossification and calcification and was, therefore, more extensively distributed in the treated tissues.
Note on the assimilation of glucose and glycine from seawater by the embryos of a sea anemone, Actinia equina
Authors: Chia Fu-Shiang
Published: August 2008

The embryos of a viviparous sea anemone, Actinia equina, take up glucose at the rate of 16.8 μg/g wet weight per hour and glycine at the rate of 8.2 μg/g wet weight per hour from the seawater. Autoradiographic studies showed that glucose was incorporated in both ectoderm and endoderm tissues whereas glycine was incorporated mostly in ectoderm tissues.
The embryology of Lytta viridana LeConte (Coleoptera: Meloidae). VIII. The respiratory system
Authors: Rempel J. G. , Church N. S.
Published: August 2008

The tracheal system arises as intrasegmental ectodermal invaginations in the anterolateral regions of the mesothorax, metathorax, and first eight abdominal segments. Dorsal, dorsal visceral, ventral visceral, and ventral tracheal branches from the spiracular tracheae form in most segments. A ventral visceral trachea is lacking in the mesothorax and a dorsal visceral in the metathorax. Before eclosion the metathoracic ventral visceral trachea disappears and the metathoracic spiracle becomes occluded. The longitudinal tracheal trunks develop after the segmental tracheae from cephalad branches from the spiracles. The ventrolateral trunk to the head supplies branches to all the cephalic appendages, including the antenna and labrum. The trachea to the prothoracic ganglion and leg probably represents the ventral trachea from a primitive prothoracic spiracle. The trachea to the suboesophageal ganglion and the cephalic ventrolateral trunk may represent branches from an original "labial" spiracle. An internal closing apparatus involves the spiracular tracheal wall and has a single opening muscle. The oenocyte bodies form by ectodermal cell proliferation in the posterolateral regions of the first eight abdominal segments.
The genus Crenosoma (Nematoda: Metastrongyloidea) in New World mammals
Authors: Craig Robin E. , Anderson Roy C.
Published: August 2008

Study of types and other specimens of Crenosoma from the lungs of carnivores indicates that there are only six known valid species in the New World, namely: C. vulpis (Dujardin 1844) Railliet 1915; C. potos Buckley 1930; C. petrowi Morozov 1939 (= ? C. schulzi Gagarin 1958); C. mephitidis Hobmaier 1941 (= C. microbursa Wallace 1941, C. zederi Goble 1942, C. canadensis Webster 1964); C. goblei Dougherty 1945; C. hermani Anderson 1962. C. petrowi is reported for the first time in the New World, in the fisher Martes pennanti Erxleben and the badger Taxidea taxus (Schreber). Sobolevingylus coloradoensis (Olsen 1952) n. comb. (= Crenosoma coloradoensis) is proposed. An illustrated key is provided for the separation of the various species.
Reproduction of Richardson's ground squirrel (Spermophilus richardsonii) in southern Saskatchewan
Authors: Sheppard D. H.
Published: August 2008

Adult Richardson's ground squirrels (n = 238) were collected near Regina, Saskatchewan in April and May of 1969 and 1970. The adult sex ratio (males: females) of collected animals was 1:3.3 compared with a juvenile sex ratio of 1:1 obtained by live trapping in 1967and 1968. The breeding season extended from 3 to 28 April but 77.8% of all conceptions occurred between 7 and 16 April. All yearlings seemed to be sexually mature and the mean litter size for all females baaed on living embryos was 6.93 ± 0.18. Mortality of embryos was 6.83%. Yearlings were smaller than adults but mean litter sizes of yearlings and adults did not differ. Ground squirrels collected from cropland had a significantly larger mean litter size, were somewhat heavier, and had significantly longer humeri than those from native grassland.
Field observations on the social relationships between adult female and juvenile Richardson's ground squirrels
Authors: Michener Gail R.
Published: August 2008

Field observations were conducted in southern Saskatchewan in 1969 and 1971. Adult female Richardson's ground squirrels and their own young engaged predominantly in nasal and cohesive contacts while adults and young from other litters engaged predominantly in agonistic contacts. Identification sometimes occurred at a distance based on the location and behavior of the other animal.Newly emerged juveniles remained close to the home burrow and engaged mainly in non-agonistic interactions with both their mothers and other adults. Not until juveniles were 6–7 weeks old and were familiar with the area used by the mother did they correctly identify adults regardless of where the interaction occurred.
Revision of the New World genus Cryptocanthon Balthasar (Coleoptera: Scarabaeidae)
Authors: Howden H. F.
Published: August 2008

The formerly monotypic genus, Cryptocanthon Balthasar, is expanded to include nine species. Cryptocanthon paradoxus Balthasar from Ecuador is the only previously described species; the eight new species are lobatus from Mexico, cristobalensis from Mexico, brevisetosus from Mexico, campbellorum from Brazil, parvus from Colombia, nebulinus from Venezuela, humidus from Colombia, and peckorum from Colombia. All of the species are illustrated and a key is included.
Tapeta lucida in bony fishes (Actinopterygii): a survey
Authors: Nicol J. A. C. , Arnott H. J. , Best A. C. G.
Published: August 2008

Bony fishes belonging to 75 families were examined for ocular tapeta lucida. The results are collated with published records, and tapeta are shown to occur in 28 families of teleostomes (Holostei and Teleostei) listed in Table 2. Except in the bigeyes Priacanthidae, they are diffuse reflectors located in the pigment epithelium. Based on chemical composition, several types can be distinguished, lipid, guanine (purine), and some others, colored yellow or light tan, of unknown composition. In several tapeta minutely examined, the reflecting material occurs as platelets (guanine type) or as minute tapetal spheres (lipid and others). The tapetum of the bigeye lies in the chorioid, it is a specular reflector containing guanine; as such it is the solitary known exemplar among teleosts.
Diapause induction in the sawfly Neodiprion rugifrons Middleton (Hymenoptera: Diprionidae)
Authors: Knerer G. , Marchant Rosemary
Published: August 2008

Neodiprion rugifrons Midd. occurs on jack pine in eastern North America, where it has a single generation per year in Ontario, but two generations in Wisconsin when spring is exceptionally mild and early. Only in this situation will the sensitive last larval instar in June receive the photoperiod of around 17 h that prevents diapause induction and allows the production of another generation, whose sensitive stage is then subjected to a short, diapause-inducing photoregime in September or October.
Some hooded seal (Cystophora cristata) sounds in March
Authors: Terhune J. M. , Ronald K.
Published: August 2008

A few underwater and in-air sounds of the hooded seal (Cystophora cristata) were recorded on the pupping areas in the Gulf of St. Lawrence. The male emits underwater calls. In air, the inflation and deflation of the adult male's proboscis produces sounds of low intensity. The adult female and the pup both have an in-air call. All of the vocalizations (except for those associated with the male proboscis) seem to be variations of a low-frequency, pulsed call.
Ultrastructure of anal papillae from a seawater mosquito larva (Aedes togoi Theobald)
Authors: Meredith J. , Phillips J. E.
Published: August 2008

Anal papillae of Aedes togoi collected from seawater pools are composed of a single cell type having extensive infolding of both apical and basal plasma membranes and containing abundant mitochondria. Involvement of these organs in active transport of some type is suggested on the basis of comparison with freshwater and salt lake species.
Crustecdysone (20-hydroxyecdysone): site of storage in the crayfish Orconectes propinquus
Authors: Carlisle D. B. , Connick R. O.
Published: August 2008

Crustecdysone is found in crayfish at all stages of the molting cycle except during anecdysis. Ecdysone can only be detected from late proecdysis through ecdysis into early metecdysis, and its biological activity never reached a 10th of that of crustecdysone. No activity could be detected at any time in the brain, the eyestalks, or the mandibular gland. At all stages (except anecdysis) a gland which is situated in the antennary segment contained active material, with a maximum in late proecdysis. At that time the total activity in the blood was higher than in the gland, and some activity could be detected in the rest of the body, perhaps in undrained blood.
Studies on insect dormancy. I. Physiology of hibernation in the larvae of the blackfly Prosimulium mysticum Peterson
Authors: Mansingh A. , Steele R. W.
Published: August 2008

Hibernation in Prosimulium mysticum is regulated by the habitat temperature. The dormant larvae maintained a low rate of respiration and survived about 20 h of oxygen deprivation. Constantly aerated water, however, is necessary for prolonged survival. Hibernation is further characterized by the presence of low amounts of trehalose and glucose and high levels of glycogen, glycerol, sorbitol, and mannitol.When hibernation was terminated, respiration was significantly increased within 1–15 h at temperatures ranging from 20 to 9 °C; at 6 °C it took a little longer. Termination oaf dormancy was also associated with appreciable depletion of polyhydric alcohols and increase in trehalose.The developing larvae could reenter dormancy after being transferred from 9 °C to temperatures below 4 °C. Respiratory adjustments were achieved within a couple of hours of exposure to the low temperatures. Polyhydric alcohols were also completely recovered within a day.The significance of these observations in relation to the status of dormancy in the blackfly is discussed.
Effects of agriculture upon populations of native passerine birds of an Alberta fescue grassland
Authors: Owens R. A. , Myres M. T.
Published: August 2008

The effects of several forms of agricultural use of native fescue (Festuca scabrella) grasslands upon populations of native passerine birds were studied in the Hand Hills of southern Alberta in 1970.Censuses of avian populations were carried out on twelve 40-acre (16.2 ha) study plots as well as on two 10-mi (16.1 km) long roadside routes. The vegetation on the study plots and along the roadside routes was described.Native fescue grasslands, undisturbed for 3 years, supported a passerine community consisting of Baird's sparrow (Ammodramus bairdii), Sprague's pipit (Anthus spragueii), savannah sparrow (Passerculus sandwichensis), clay-colored sparrow (Spizella pallida), and western meadowlark (Sturnella neglecta). Incomplete disturbance of fescue grasslands, by mowing for hay or grazing by cattle, reduced or eliminated Baird's sparrow and Sprague's pipit but permitted the ingress of horned lark (Eremophila alpestris) and chestnut-collared longspur (Calcarius ornatus). Total elimination of the native grassland, by ploughing and cultivation for cereal crops, eliminated all passerine species except the horned lark. Peripheral disturbed areas resulting from cultivation, such as held boundaries and roadside ditches, may have benefited several species that tend to occur in ecotonal habitats: savannah sparrow, clay-colored sparrow, and vesper sparrow (Pooecetes gramineus).
Studies on helminths of North Dakota. VII. Ancyrocephalinae (Monogenea) from the gills of the blue sucker, Cycleptus elongatus (LeSueur)
Authors: Leiby P. D. , Kritsky D. C. , Bauman D. D.
Published: August 2008

Two species, Anonchohaptor olseni sp. n., and Myzotrema cyclepti Rogers, 1967, are reported from Cycleptus elongatus (LeSueur) from the Missouri River in North Dakota. Anonchohaptor olseni sp. n. is figured and described. It differs from its closest relative, A. muelleri Kritsky et al., 1972, principally in the morphology of the hooks, cirrus, and accessory piece. Myzotrema cyclepti is reported for the first time from North Dakota.
A procedure for short-term bioassay tests on industrial effluents of low oxygen content
Authors: Ozburn G. , Kraft J. , Somppi L.
Published: August 2008

Oxygenation of industrial effluents with a low dissolved oxygen content has been achieved by a method which greatly reduces the possibility of stripping volatile toxins within the effluent. The decrease in toxicity that occurs if a sample is aerated with a bubbler before testing can be shown clearly with this procedure.
Migration and development of Trichobilharzia ocellata (Trematoda: Schistosomatidae) in its duck hosts
Authors: Bourns T. K. R. , Ellis James C. , Rau Manfred E.
Published: August 2008

Migration and development of Trichobilharzia ocellata in ducks was studied by examining tissues and perfusate from birds which had been exposed to cercariae 5 min to 370 days earlier. Cercariae penetrated rapidly and were carried to viscera within 24 h. In the lungs, schistosomula left the vascular system to occupy air spaces, later to reenter veins in bronchial tissue. In the liver, worms were predominantly in sinusoids on days 1–6, in veins on days 7–9, and absent on days 10 and 11. Small numbers returned to the liver, which was the only organ harboring worms between days 89 and 370. Most worms found between days 10 and 21 were in the veins and tissues of the gut but none were there after day 21. Oviposition began on day 9, and peak numbers of eggs were found in the gut wall on days 14–16. Growth and development of T. ocellata were rapid. Caecal union was complete by day 2, organogeny by day 4, gametogeny by day 6, and sexual maturity and adult size by day 7. Morphological description of developing forms and of adults are given, the latter based upon examination of forty 9-day-old specimens of each sex.
Morphological variation and status of the orioles, Icterus galbula, I. bullockii, and I. abeillei, in the northern Great Plains and in Durango, Mexico
Authors: Rising James D.
Published: August 2008

The phenetic affinities of 56 specimens of the orioles Icterus galbula and I. bullockii, and specimens intermediate between them, from the northern Great Plains, are discussed. Phenetically intermediate individuals appear there in lower proportion than they do at most localities in the southern plains, suggesting that there is selection against such individuals in the north. The range of I. galbula seems to be extending southward m the northern plains at the expense of I. bullockii; this is possibly correlated with changes in the climatic environment. I. bullockii and I. abeillei both are uncommon in north-central Durango, Mexico, the only place where they are known to be sympatric.
On the anatomy and affinities of Nesion arcticum Hyman, a marine triclad from Alaska (Platyhelminthes: Turbellaria)
Authors: Ball Ian R.
Published: August 2008

Nesion arcticum, a marine triclad from Alaska, is redescribed from the type material. The family Nesionidae is abolished and it is argued that the closest extant relatives of Nesion are the aberrant monolypic genera Miroplana and Ectoplana, known only from Japan. Pending a revision of the aquatic triclads all three genera are classified within the family Procerodidae. The genus Tiddles, from Brazil, was originally assigned to the Nesionidae, which necessitated a redefinition of the family, but it is not closely related to Nesion, and it does not belong in the same family.
The fine structure of the esophagus of some trichuroid nematodes. II. The buccal capsule and anterior esophagus of Capillaria hepatica (Bancroft, 1893)
Authors: Wright K. A.
Published: August 2008

The anterior alimentary tract of Capillaria hepatica participates in formation of the buccal capsule and shows different cellular organization along its length. The buccal capsule is composed of both invaginated body-wall cuticle (stomodeum) and the expanded anterior esophageal cuticle and contains a small dorsal stylet. Suction action of the buccal capsule is controlled by two sets of buccal dilator muscles and three esophageal suspensor muscles. The anteriormost esophagus consists of three elongate marginal cells and three units of radial tissue. At the level of the nerve ring, radial tissue divides into six units, two between each marginal cell. Posterior to the nerve ring, the esophagus is surrounded by a muscle sheath that continues for the rest of the esophagus. Radial tissue has both longitudinal and radial myofilaments, as does the midregion of marginal cells. Marginal cells terminate some distance posterior to the nerve ring and radial-tissue units fuse to form a single cytoplasmic mass around the cuticle. Posteriorly, myofilaments are reduced from the radial tissue. Peristalsis of the esophagus is probably maintained by the outer muscle sheath. Three nerve cells are located in the wall of the esophagus, posterior to die level of marginal cells, and send processes both anteriorly and posteriorly. Synapses between axons and radial tissue have been identified only in the anterior esophagus. Because of the degree of organization of myofilaments, and the presence of sacroplasmic reticulum diads and synapses, it is suggested that the region of the esophagus just posterior to the nerve ring may serve as a pacemaker region for esophageal activity. Three satellite cells located in the anterior esophagus may represent vestigial stylet retractor muscles.
The effects of temperature and ultraviolet radiation on the infection of Choristoneura fumiferana and Malacosoma pluviale by a microsporidan parasite, Nosema (Perezia) fumiferanae (Thom.)
Authors: Wilson Gary G.
Published: August 2008

The effects of temperature and ultraviolet radiation on the biology of Nosema fumiferanae and its host, Choristoneura fumiferana, were investigated. The temperature at which the host is reared has a definite effect on the parasitic microsporidan. Temperatures above 23 °C are detrimental to the parasite and temperatures above 28 °C are detrimental to the host as well. Spores of N. fumiferanae become inactivated by 5 to 6 h of exposure to sunlight, or 3 to 4 h of exposure to a 30-W germicidal (ultraviolet) light.
Redescription of Neomesomermis flumenalis (Nematoda) from blackflies in Newfoundland
Authors: Ebsary Barry A. , Bennett Gordon F.
Published: August 2008

Neomesomermis flumenalis, a mermithid parasite of North American simuliids, is described from Newfoundland blackflies. The eggs and preparasitic stages of this mermithid have not previously been encountered.
Observations on chick-embryo lens histogenesis in vivo and in vitro
Authors: McLean Brian G. , Finnegan Cyril V.
Published: August 2008

The 6-day chick-embryo lens anterior epithelium will undergo histogenesis in vitro. A 'normal' epithelial curvature in vitro is required for extensive fiber-cell elongation; a reversed curvature, or flat epithelial conformation, results in considerably reduced cell extension. With a 'normal' epithelial curvature, cell elongation in vitro progresses rapidly for about 3 days, and changes in cytoplasmic organization (ultrastructure) take place that are similar to those associated with fiber-cell differentiation in vivo. However, these cells do not achieve as full a cytoplasmic differentiation as was observed in the most differentiated cells of the normal embryonic lens. Epithelia explanted with a reversed curvature, while evidencing reduced cell elongation, had, after 3 days in vitro, differentiated (according to criteria of ultrastructure and relative proportions of soluble proteins) in a manner similar to those epithelia explanted with a 'normal' curvature and in which extensive cell elongation had been demonstrated.
Bulbodacnitis alpinus sp. nov. (Nematoda: Cucullanidae) from Arctic char, Salvelinus alpinus L., with notes on other species of Bulbodacnitis
Authors: Mudry Dwight R. , McCart Peter
Published: August 2008

Bulbodacnitis alpinus sp. nov. is described from Salvelinus alpinus L. from the North Slope of Yukon and Alaska. Bulbodacnitis alpinus was found to be present in both anadromous and freshwater resident stream populations but it is absent from lake populations of S. alpinus. Specimens of B. occidentalis Smedley, 1933, B. scotti Simon, 1935, B. ampullastoma Maggenti, 1971, and B. truttae (Fabricius, 1794) were examined and comparative measurements are presented. Bulbodacnitis scotti, B. ampullastoma, and B. occidentalis are considered synonyms of B. truttae.
Bioenergetics and growth of largemouth bass (Micropterus salmoides) in relation to body weight and temperature
Authors: Niimi A. J. , Beamish F. W. H.
Published: August 2008

Changes in growth and proximate body composition of largemouth bass (Micropterus salmoides) were examined for fish of 8–150 g, between 18 and 30C. For most weights, growth of fish (grams/day) was highest at 25C, and lowest in fish at 18C. This was attributable in part to a higher satiation (maximum) feeding level at 25C. For a fixed level of feeding, growth rate (percentage wet weight/day) was highest for fish held at 18C.Lipid content (percentage wet weight) increased with feeding level and was highest at 18C, Moisture content varied inversely with lipid. Protein and ash content did not vary appreciably with temperature, body weight, or feeding level.Maintenance requirement of bass, expressed as grams/day, was about twice that lost during food deprivation, but only slightly different when expressed as kilocalories/day.Energy requirements for nonfecal losses were estimated as 10% of intake energy at all feeding levels. Standard metabolism accounted for 50% of intake energy near maintenance, but only 10% at the satiation feeding level. Growth requirements increased From zero at maintenance to 40% of intake energy at satiation feeding.
Hemocytes of Malacosoma disstria Hübner (Lepidoptera: Lasiocampidae): morphology of the cells in fresh blood and after cultivation in vitro
Authors: Arnold J. W. , Sohi S. S.
Published: August 2008

Hemocytes of the forest tent caterpillar, Malacosoma disstria, were examined in blood films prepared from full-grown larvae, and in tissue cultures of blood cells maintained by serial passage in vitro up to 148 times. In fresh larval blood, five categories of hemocytes were identified as follows: prohemocytes, plasmatocytes, granular hemocytes, spherule cells, and oenocytoids. The granular hemocytes were the most numerous by far. In the tissue cultures, only three categories were found, prohemocytes, plasmatocytes, and granular hemocytes. and here the granular hemocytes were the least numerous. Each category in culture was autonomous and able to divide. Hemocytes in cultures were larger than the cells in fresh blood, and were mostly round.
Migration, overwintering, and reproductive patterns of Taricha granulosa on southern Vancouver Island
Authors: Oliver M. G. , McCurdy H. M.
Published: August 2008

Sexual dichotomy in habitat selection during the nonbreeding season was studied in the rough-skinned newt Taricha granulosa from November 1970 to August 1973 on southern Vancouver Island. Field results show that in this area adult females normally migrate from breeding ponds to overwinter on land. Adult males normally remain permanently aquatic. Related observations on the reproductive cycle of T. granulosa show that females, who lay their eggs singly, deposit them for a period of a few days, followed by a period of nonegglaying. This process is repeated at intervals. Oviposition can occur from late April to July in this area. Females who were induced to ovulate in the laboratory each deposited three eggs per day for 5 days before opposition ceased. Thus the reproductive cycles of field and taboratory-acclimated females are correlated.
A laboratory study of the effects of some climatic factors on the demography of the terrestrial isopod Porcellio spinicornis Say
Authors: McQueen D. J. , Carnio J. S.
Published: August 2008

The demography of Porcellio spinicornis was modelled using growth, survival, and reproduction parameters modified by temperature, humidity, and day length. Growth rates were temperature-dependent (0.0 below 10 °C, increasing to a maximum at 30 °C, and decreasing to 0.0 above 35 °C). Survival rates were both temperature-dependent and size-dependent. Small animals (prejuveniles) survived between 10 °C and 35 °C with maximum survival at 25 °C. Medium-sized animals (juveniles) and adults survived between 0° and 35 °C with maximum survival at 25 °C. Females were able to reproduce between 17.5 °C and 27.5 °C, and the number of young produced increased with female size. P. spinicornis exhibited narrow humidity tolerances (95% RH ± 3% RH) but were able to search out and remain in microhabitats containing the correct humidity conditions. Day length had no detectable demographic effects.Simulations using the laboratory-based demographic model and field temperatures for 1971 and 1972 suggested that a P. spinicornis population should slowly increase in numbers. But when the 1971–1972 temperatures were decreased by art average of 0.77 °C, the simulated population decreased. This suggests that minor temperature fluctuations could regulate the numbers of P. spinicornis; and inspection of field temperature data from 1957–1973 indicates sufficient year to year temperature fluctuation to maintain stable P. spinicornis populations in Southern Ontario.
Survival of embryos, tadpoles, and adults of the frogs Rana aurora aurora and Rana pretiosa pretiosa sympatric in southwestern British Columbia
Authors: Licht Lawrence E.
Published: August 2008

Field survival of embryos, tadpoles, and adults of Rana aurora and Rana pretiosa sympatric in marshes near Vancouver, British Columbia, was studied.Embryonic survival for R. aurora was 90% and better, whereas for R. pretiosa it was about 70%. As well, in dry periods during breeding, R. pretiosa embryos face the danger of desiccation and extensive or complete mortality.Survival of tadpoles of both species in a pond breeding site studied was less than 1% in 1968. By the end of the season of transformation, there was about 5% survival of young-of-the-year frogs of both species from the initial number of eggs deposited in river breeding sites.After the end of the first full year of life (1969), there was a minimal survival of 2.5% for R. aurora and 3.5% for R. pretiosa from the eggs laid the year before. By the end of 1969, there was a 52% survival of R. aurora and 67% of R. pretiosa which metamorphosed in 1968.For R. pretiosa adults, there was a 64% survival between 1968 and 1969; males suffered higher mortality than females. The survival of adult R. aurora was 69% between 1968 and 1969.Factors influencing mortality are discussed, and the conclusion is reached that predation (and chance climatic events for R. pretiosa embryos) on all life-history forms is the strongest factor limiting frog population numbers.
Studies on insect dormancy. II. Relationship of cold-hardiness to diapause and quiescence in the eastern tent caterpillar, Malacosoma americanum (Fab.), (Lasiocampidae: Lepidoptera)
Authors: Mansingh Ajai
Published: August 2008

Studies were conducted on the relationship between levels of glycerol and carbohydrates, supercooling points, and the relative abilities of diapausing and developing eggs and of larval instars of Malacosoma americanum to withstand various periods of chilling at 5° and −15 °C.Diapause in the mature embryos was associated with very high glycerol content (112 mg/g), low carbohydrate level (13 mg/g), and the ability to supercool to −35 °C. During diapause termination, the glycerol level was reduced lo 11 mg/g with a slight rise only in carbohydrate level while the supercooling point was raised to −14 °C. When quiescence was induced in the larvae by chilling them at 5 °C for 1 to 7 weeks, their wet weights and carbohydrate and glycerol contents decreased gradually. However, the supercooling point remained constant around −14 °C.Diapausing embryos could survive several weeks of chilling at −15° and 5 °C. However, only a few weeks of exposure to 5 °C was fatal to quiescent larvae.It is concluded that there is a direct relationship between glycerol content, supercooling points, and the relative abilities of developing and diapausing stages of the tent caterpillar to withstand low temperatures. The developing stages were naturally "cold-tolerant" with the ability to supercool to −14 °C and survive a few weeks of quiescence at 5 °C, which is well below their range of physiological adaptation. Induction of diapause enhanced the supercooling ability and increased cold-hardiness in the mature embryos.
Presence of Dicrocoelium dendriticum (Rudolphi, 1819) (Trematoda: Dicrocoeliidae) in western Canada
Authors: Lewis Jr. Paul D.
Published: August 2008

Dicrocoelium dendriticum is reported for the first time in western Canada. Nearly 4000 worms were obtained from the bile ducts of two British Columbia cattle slaughtered in Lethbridge, Alberta in April, 1973. On the basis of unpublished records, it appears that D. dendriticum occurs in three localities in British Columbia, and has been known since 1965.
Territorial behavior of juvenile Atlantic salmon reduces predation by brook trout
Authors: Symons Philip E. K.
Published: August 2008

Brook trout (Salvelinus fontinalis) ate 26% of 58 juvenile (7–11 cm) Atlantic salmon (Salmo salar) introduced into an artificial stream 24 h before the trout, but they ate only 8% of 60 salmon which had been present long enough to establish territories. Man-made environmental alterations may decrease territorial behavior of young salmon thereby increasing their vulnerability to predation.
Ultrastructure of sex-pheromone gland cells and cuticle before and during release of pheromone in female eastern spruce budworm, Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae)
Authors: Percy Jean E.
Published: August 2008

The sex-pheromone-producing gland of Choristoneura fumiferana, as in other moths, is a modified intersegmental membrane between the eighth and ninth abdominal segments. Gland cells differ from epidermal cells in unmodified intersegmental membranes in their size, shape, and structure. One to 2 days before emergence of the adult, the gland cells have few microvilli and the cytoplasm contains mainly rough endoplasmic reticulum. By 1 h before emergence, the cells have the adult characteristics. The basal region below the nucleus contains Golgi complexes, lipid droplets, glycogen deposits, and rough endoplasmic reticulum. The apical region contains many microbodies and extensive smooth tubular endoplasmic reticulum. The apical surface has numerous well-developed microvilli, each of which contains a core of smooth endoplasmic reticulum. In contrast to gland cells, unmodified epidermal cells only contain rough endoplasmic reticulum and their apical projections are small and ill-defined. Cuticle of the gland and unmodified intersegmental membrane does not change after deposition but continues to resemble that of the developing gland 1 to 2 days before emergence. Pore canals are present as gaps in the endocuticle and follow the helicoidal arrangement of the microfibrils. Near the microvilli the pore canals contain a filamentous structure which is replaced by epicuticular filaments near the first lamella of the endocuticle. Groups of epicuticular filaments terminate at an oval depression in the dense epicuticle. Each oval depression opens at the surface of the inner cuticulin. Epicuticular filaments are not the immediate precursors of the pheromone. The probable role of the epicuticular filaments in pheromone synthesis and release is discussed.
A revision of Helicometra Odhner, 1902 and related genera (Trematoda: Opecoelidae), including a description of Neohelicometra sebastis n. sp.
Authors: Sekerak Aaron D. , Arai Hisao P.
Published: August 2008

The genera Helicometra Odhner, 1902, Neohelicometra Siddiqi and Cable, 1960, Stenopera Manter, 1933, and Allostenopera Baeva, 1968 are reviewed and the species therein evaluated in consideration of pronounced morphological variations in H. pulchella (Rudolphi, 1819) Odhner, 1902 and other species of these genera. Species possessing a terminal, funnel-shaped oral sucker are transferred to Neohelicometra. Stenopera and Allostenopera are considered invalid. New synonyms include: H. hypodytis Yamaguti, 1934; H. dochmosorchis Manter and Pritchard, 1960; H. aposinuata Pritchard, 1966; H. upapalu Yamaguti, 1970 = H. pulchella; H. neosebastodis Crowcroft, 1947 = H. tenuifolia Woolcock, 1935; H. boseli Nagaty, 1956 = H. equilata (Manter, 1933) Siddiqi and Cable, 1960; H. rectisaccus (Fischthal and Kuntz, 1964) Fischthal and Kuntz, 1965 = H. nasae Nagaty and Abdel Aal, 1962; and H. pugetensis Schell, 1973 = N. pleurogrammi (Baeva, 1968) n. comb. Neohelicometra sebastis n. sp. is described from various species of rockfishes (Sebastes) from the northeastern Pacific. The other species of the genus, Neohelicometra antarcticae (Holloway and Bier, 1968) n. comb; N. pleurogrammi (Baeva, 1968) n. comb.; N. insolita (Polyansky, 1955) n. comb.; and N. scorpaenae Siddiqi and Cable, 1960, possess a cirrus sac which does not extend posterior to the acetabulum, whereas that of N. sebastis normally extends to the miduterine level. A key to the species of Helicometra and Neohelicometra is included.
Effects of 17α-methyltestosterone on the dorsal pad and tubercles of fathead minnows (Pimephales promelas)
Authors: Smith R. J. F.
Published: August 2008

The formation of breeding tubercles and a mucus-secreting dorsal pad in male and female fathead minnows is induced by 17α-methyltestosterone. Neither lactotrophic hormone (LTH) nor human chorionic gonadotropin induced dorsal pad or tubercle formation in the dosages used. LTH (with androgen) may delay loss of mucus cells at the end of the breeding season.
Energy metabolism of oiled muskrats
Authors: McEwan E. H. , Aitchison N. , Whitehead P. E.
Published: August 2008

The heat production of muskrats (Ondatra zibethica), oiled with varying quantities of crude oil, was measured at three ambient temperatures, −5, 5, and 10C on days 0, 1, and 3 after oiling. On day 0, the heat production of muskrats oiled with 1.9 to 42.3 g of oil was from 14 to 119% higher, respectively, than the non-oiled muskrats. Three days after oiling, the metabolic rate of oiled muskrats was about the same as the control values. A similar trend was determined for ambient temperatures of 5 and 10C. Heavy oiling increased the thermal conduction of muskrats by as much as 122%. To compensate for the loss of insulation and increased thermal conductivity of the fur, there was a 2.5-fold increase in dry-matter intake. In view of their dependence on water, both for feeding activities and a place for refuge, it is doubtful if muskrats exposed to moderate quantities of oil could survive under natural conditions.
Seasonal changes in the thyroid proteinase of a teleost fish, the burbot, Lota lota L.
Authors: Wiggs Alfred J.
Published: August 2008

Proteolytic activity extracted from thyroid tissue was studied over the course of a year. The pH curves of enzyme prepared from fish collected in winter and spring were basically alike and showed three peaks of activity. The thermal stabilities, Michaelis constants, and iodoacetate sensitivity suggest that the enzymes prepared from fish in winter and spring were different. Furthermore, the ratios of activities at the three peak pH values are not constant.The proteolytic activity assayed at the optimum pH 2.5 showed a significant increase in June.
New records of the mysids Boreomysis nobilis G. O. Sars and Mysis litoralis (Banner) in the Saguenay fjord (St. Lawrence estuary)
Authors: Judkins David C. , Wright Robert
Published: August 2008

The arctic–subarctic mysids Boreomysis nobilis and Mysis litoralis were abundant in midwater trawl collections from the Saguenay fjord but were almost absent in collections from the confluent St. Lawrence estuary and Gulf of St. Lawrence. Collections from the estuary and Gulf contained boreal mysids more typical of the latitude. The presence of apparently isolated populations of B. nobilis and M. litoralis in the fjord is further evidence that it is an arctic enclave within a boreal region. The hypothesis that populations of arctic and subarctic species in the Saguenay fjord are relicts from a previous glacial period is questioned in view of the possibility of more recent faunal exchange between the Arctic and the fjord via intermediate arctic enclaves on the eastern Canadian coast.
Size at onset of sexual maturity and growth rate in crustacean populations
Authors: Wenner Adrian M. , Fusaro Craig , Oaten Allan
Published: August 2008

The size at which crustaceans become mature can be a useful gauge in the study of environmental effects on field populations. The use of probability paper in rigorously defining the mean size at onset of sexual maturity avoids some of the confusion inherent in other methods of assessing size at maturity and permits an objective comparison of differences between discrete populations. Both logical and mathematical considerations in the use of probability paper for analyzing field data have been treated; and some sample data reveal how one might detect environmental effects on population structure. In this case the data indicated that mole crabs (Emerita analoga) may have grown at different rates in proximate populations.
A redescription of Paradilepis longivaginosus (Mayhew, 1925) (Cestoda: Dilepididae) and a comparison with Paradilepis simoni Rausch, 1949 and Paradilepis rugovaginosus Freeman, 1954
Authors: McLaughlin J. Daniel
Published: August 2008

Paradilepis longivaginosus (Mayhew, 1925) is redescribed from fresh material, and the systematic position of P. longivaginosus, Paradilepis simoni Rausch, 1949, and Paradilepis rugovaginosus Freeman, 1954 is discussed in light of the new morphological data. The three species can be readily separated by two prominent distinguishing features: the number and size of the rostellar hooks, and the structure of the vagina.
Structure of an air-breathing organ and the swim bladder in the Alaska blackfish, Dallia pectoralis Bean
Authors: Crawford R. H.
Published: August 2008

Specimens of the Alaska blackfish, Dallia pectoralis Bean, were examined for an air-breathing organ. The swim bladder is modified for gas secretion, with rete mirabile and gas gland. However, the swim bladder lacks epithelial capillaries, as found in the mudminnows (Umbra). Further examination of the digestive tract has shown that the oesophagus is modified as an accessory respiratory organ. There is a sphincter between the oesophagus and stomach. Blood supply is from a branch of the coeliac artery, and venous blood from the oesophagus enters the anterior sections of the postcardinal veins. The blood vessels extend to the oesophageal epithelium, with an extensive arrangement of epithelial capillaries in the respiratory section of the oesophagus. The muscularis externa of the oesophagus is well developed, consisting of an outer transverse layer of striated muscle and inner longitudinal muscle bundles.
Population dynamics of cladocerans in Sunfish Lake, Ontario
Authors: Clark A. S. , Carter J. C. H.
Published: August 2008

Investigation of populations of Daphnia rosea, D. retrocurva, and Diaphanosoma leuchtenbergianum in Sunfish Lake, southern Ontario, during 1969 indicated that, in the absence of predation, food supply was the major factor controlling population size and influencing population parameters. Generally with each species, a population peak was preceded by a rise in fecundity, an increase in birth rate, and a fall in death rate. As the carrying capacity of the environment in terms of food was surpassed the population numbers declined, fecundity dropped off, and the death rate rose. A strong negative correlation between fecundity and death rate was observed.
Inhibition of molting of the desert locust, Schistocerca gregaria, by the nematode parasite Mermis nigrescens
Authors: Craig S. M. , Webster J. M.
Published: August 2008

The older the host (Schistocerca gregaria) at infection, the greater the burden of parasitic Mermis nigrescens required to inhibit the next-but-one molt. Mermithid parasitism caused no change in ecdysone level in the host, but did cause a decrease in fat body protein synthesis. The effect of this decrease on host molting is discussed.
Records of Siphonaptera (Insecta) from birds' nests in Newfoundland
Authors: Phipps J. , Bennett G. F.
Published: August 2008

Ceratophyllus gallinae (Schrank), C. diffinis Jordan and C. idius Jord. and Roths. were collected from vacated nests of passerine birds in Newfoundland.
Macroinfauna of northern New England marine sand. II. Amphipod-dominated intertidal communities
Authors: Croker R. A. , Hager R. P. , Scott K. J.
Published: August 2008

This is a 5-year study of macroinfaunal communities of moderately exposed to sheltered intertidal sands of New Hampshire and southwestern Maine. Habitats also differed in slope, width, predominant sand grain size, and carbon–nitrogen concentrations. Thirty-one species were recorded. Abundance and dry weight biomass at four intensively studied habitats averaged 5000/m2 and 2.1 g/m2, respectively, during 1971. The most exposed habitat yielded twice this standing crop, correlated with intermediate levels of carbon and nitrogen. Over 90% of seasonal numbers and biomass at more exposed habitats were attributable to six species of relatively short-lived amphipods, mostly Haustoriidae. Between-habit at variation in abundance and biomass of amphipods was in general greater than seasonal variation within habitats. Polychaete species increased at sheltered habitats, and bivalve mollusks were restricted to shelter. The typical community of moderately exposed sands south of Penobscot Bay, Maine, is characterized by a recurrent group of nine species (five amphipods). Community stability is assisted by brooding habits of dominant amphipods. Zonation, subtidal connections, seasonal movements, and patterns of amphipod species dominance are discussed. Structural comparisons are made with boreal European and other Atlantic coast intertidal sand communities.
Gastrointestinal parasites of the cave salamander, Eurycea lucifuga Rafinesque, from the southeastern United States
Authors: Dyer William G. , Peck Stewart B.
Published: August 2008

The gastrointestinal tracts of 255 cave salamanders, Eurycea lucifuga Rafinesque, from Alabama, Georgia, Illinois, Kentucky. Missouri, Tennessee, Virginia, and West Virginia were examined for parasites. Parasites recovered from 114 (44.7%) salamanders included: Prolozoa—Haptophyra gigantea Maupas, 1879; Trematoda—Brachycoelium sp.; *Cainocreadium pseudotritoni (Rankin, 1937) Yamaguti, 1958; Cestoda—*Batrachotaenia cryptobranchi (La Rue, 1914) Freze, 1965; Nematoda—*Capillaria inequalis Walton, 1935; Cosmocercoides dukae (Hull, 1928) Wilkie, 1930; *Omeia papillocauda Rankin, 1937; *Oswaldocruzia pipiens Walton, 1929; *Rhabdias sp.; *Thelandros magnavulvaris (Rankin, 1937) Schad, 1960; and spirurid cysts. An asterisk (*) preceding the parasite name indicates a new host record.
Reproductive timing by the polychaetes Clymenella torquata and Praxillella praetermissa in Passamaquoddy Bay, New Brunswick
Authors: Rowe V. Leslie , Hynes H. B. N. , Tyler A. V.
Published: August 2008

Two species of polychaete, Clymenella torquata and Praxillella praetermissa, are able to maintain sufficient numerical stability to be a regular food item of fish in Passamaquoddy Bay, New Brunswick. Each species is living near an extreme of its distribution in Passamaquoddy Bay and this has necessitated adaptations in habitat and in reproductive biology. Clymenella spawn at the same temperature as do populations to the south but later in the summer. Praxillella, an Arctic species, spawns during winter.
An all-weather reindeer locator system
Authors: Dieterich R. A. , Holleman D. F. , Luick J. R.
Published: August 2008

A radiotelemetry system for locating reindeer during both clear and overcast weather conditions was tested using reindeer fitted with transmitters and a light aircraft equipped with a directional receiver. The aircraft was guided to the reindeer by the transmitter signal and subsequently the position of the aircraft was determined by aviation navigational aids. Under simulated overcast weather conditions, reindeer were located within a circle of 3000 m radius. This accuracy was more than adequate to locate members of a herd so that a herder could be directed to his reindeer.
Lymphoid cell adherence in Protostrongylus (Nematoda: Metastrongyloidea) infections of Rocky Mountain bighorn sheep
Authors: Hudson R. J.
Published: August 2008

Lymphoid cells obtained from peripheral blood of Rocky Mountain bighorn sheep adhered in vitro to first-stage Protostrongylus larvae. Indirect evidence suggested that the reaction was dependent on small amounts of weakly or noncytophilic antibody. Minimally diluted whole serum and serum fractions from parasitized animals blocked cell adherence at concentrations higher than those required for sensitization in a phenomenon reminiscent of immunologic enhancement in tumor and transplantation immunology. Serum fractions from sheep and sera from man, rabbit, and chinchilla also inhibited lymphoid cell adherence, although to a lesser extent than gamma-globulin from parasitized bighorn sheep.
Contributions to a revision of the marine triclads of North America: the monotypic genera Nexilis, Nesion, and Foviella (Turbellaria: Tricladida)
Authors: Ball Ian R.
Published: August 2008

New interpretations of the anatomy and systematic positions of three North American marine triclads are given. Nexilis epichitonius is redescribed from the type material and it is claimed that the original interpretation of the copulatory apparatus was erroneous. A new account is given, the genus is redefined, and some curious similarities between this species and some triclads of Lake Baikal are discussed. A further assessment of the taxonomic affinities of Nesion arcticum is provided based on study of a new specimen that is better preserved than the types. The systematic position of Foviella affinis is discussed on the basis of studies of specimens from North America and Europe. The species cannot be a procerodid and it is here classified with the Uteriporidae. Probursa and Centrovarioplana are removed from the Uteriporidae and the family is redefined.