bluuebunny/crossref_metadata_2025 huggingface dataset:
Upper lethal temperatures of the pelecypod Modiolus demissus in relation to declining environmental temperatures
Authors: Waugh D. L.
Published: August 2008

Determinations of 24-h upper lethal temperatures of the ribbed mussel Modiolus demissus (Dillwyn) in relation to declining autumn and winter habitat temperatures show effective thermal acclimatization. Upper lethal temperatures ranged from 39.48 ± 0.33C to 37.67 ± 0.08C and the descending range of mean monthly environmental temperature was from 25C to −1.1C. Environmental and test salinity ranged from 28 to 30‰.The regression of lethal temperature on acclimatization temperature is significant when a direct correlation (concomitant) is made between ambient temperature and lethal temperature. Thus, current ambient temperature is an accurate reflection of acclimatization in this species.
Sex chromatin in avian species
Authors: Bhatnagar M. K.
Published: August 2008

A comparison of nuclear chromatin bodies in squash preparations of interphase cell nuclei of white Chinese geese (Cygnopsis cygnoid), domestic ducks (Anas platyrynchos var. domestica), and domestic chicken (Gallus domesticus) with those of ferret (Putorius furo) embryonic cells from skin, gastrointestinal muscularis, kidney, and spinal cord was made using buffered thionin staining method. No definite planoconvex chromatin mass was detectable in avian female or male cell nuclei in any of the four tissues, whereas in mammalian tissue (ferret) used as controls the nuclei from female embryonic cells consistently showed a preponderance of typical sex chromatin bodies.The autoradiographic studies on 3H-thymidine labeled interphase nuclei of geese fibroblast culture cells revealed no definite or dense localization of label on any particular chromatin body in either females or males. It is therefore suggested that avian somatic cells can not be sexed using sex chromatin body as a criterion.
Ovary development of worker honeybees when separated from worker brood by various methods
Authors: Jay S. C.
Published: August 2008

Ovary development of workers increased progressively with the following treatments: (a) with queen, with brood or without queen, with brood; (b) with queen (confined or free), without brood; (c) without queen, without brood.Ovary development of queenless, broodless workers separated from worker larvae (or pupae) by single or double screens was similar, but was significantly higher than that of queenright workers with brood (controls) and significantly lower than that of queenless, broodless workers; possibly a volatile brood (or brood-related) scent was acting to inhibit ovary development in these workers.
Morphology, life history, and ecology of an unusual stickleback (Gasterosteus aculeatus) in the Queen Charlotte Islands, Canada
Authors: Moodie G. E. E.
Published: August 2008

In Mayer Lake Black sticklebacks shared an exposed environment with several predatory fish, whereas leiurus, the typical freshwater form of Gasterosteus aculeatus, was the only fish inhabiting the vegetation-choked margins of the inlet streams and stream mouths. Black sticklebacks and, to a lesser extent, leiurus were seldom collected outside their respective habitats. Breeding Black males were probably at least 2 years old. They preferred to nest near vegetation, on sandy, gently sloping substrates. The length of the breeding season and the number of breeding cycles in the season were similar to those of other populations. Males of different phenotypes appeared to nest in habitats differing in water depth and proximity to shelter. Some differences in habitat of the nest site were seemingly correlated with breeding success. Black sticklebacks are distinguished from leiurus by their large size and pelvic spines; high gill raker, vertebral and lateral plate counts; streamlined shape; melanism and drab breeding colors. Black sticklebacks probably meet the requirements of a biologically defined species.
Idotea (Idotea) obscura, a new species of Idoteidae (Isopoda, Valvifera) from the North American Pacific coast
Authors: Rafi F.
Published: August 2008

Idotea (Idotea) obscura n. sp. is characterized by a deeply concave supra-antennal line, 12–15 flagellar articles on antenna 2, absence of setae on the outer border of maxillipedal palp segment 4, three long plumose setae on outer border of basipodite of maxilliped, epimera of pereonite 6 occupying the entire lateral margin, and an elongate, pointed median projection of the pleotelson. This species is closely related to Idotea (I.) fewkesi and Idotea (I.) ochotensis, and is found in both open and protected coast lines from North of Goshen Island, British Columbia to Port Gravina, Alaska in the intertidal zone to about 21 m depth.
Blood chemistry of the brown bear (Ursus arctos) from southwestern Yukon Territory, Canada
Authors: Halloran Donal W. , Pearson Arthur M.
Published: August 2008

Blood samples from 22 brown bears (Ursus arctos) were assayed for calcium, phosphorus, glucose, urea, creatinine, uric acid, cholesterol, total protein, albumin, total bilirubin, alkaline phosphatase, lactic dehydrogenase, glutamic–oxaloacetic acid transaminase, sodium, potassium, and chloride.Statistically significant seasonal changes in brown bears included a spring-to-summer decrease of calcium, urea, creatinine, and uric acid and concurrent increases of glucose and potassium. These changes may be related to renal function and seasonal variations in the bear's diet. The only sexual difference was the higher uric acid levels in male brown bears than in females.The blood chemistry of four black bears (Ursus americanus) was similar to that of brown bears except for slightly higher levels of phosphorus, creatinine, uric acid, glutamic–oxaloacetic acid transaminase, sodium, and chloride. Our limited sample of black bears did not allow an investigation of seasonal changes.
Further studies on the chipmunk warble, Cuterebra emasculator (Diptera: Cuterebridae)
Authors: Bennett Gordon F.
Published: August 2008

The prevalence of Cuterebra emasculator Fitch in 1328 chipmunks (Tamias striatus) was analyzed as to the sex and age class of the host and to the forest habitats from which the chipmunks were obtained. The prevalence of the parasite was highest in immature animals of both sexes and lowest in adult females. Prevalence of C. emasculator was highest in chipmunks from second-growth mixed forests; such animals also carried more parasites per animal. Chipmunks from mature coniferous forests harbored the fewest parasites per individual and the prevalence was the lowest. The parasite density was extremely low, averaging one fly per 2.8 acres in mature coniferous forest and one fly per 0.7 acres in the second-growth forest habitat.
Differential activity in the coxo-subalar muscle during directional flight in the milkweed bug, Oncopeltus
Authors: Govind C. K.
Published: August 2008

Turning movements in fixed flight in the milkweed bug, Oncopeltus, are brought about by asymmetrical alteration of the wing amplitudes of the two sides. Extracellular recordings were obtained from the direct non-fibrillar coxo-subalar muscle during directional changes in flight. The muscle is differentially activated on the two sides, such that during a right turn the frequency of nerve impulses increased in the right muscle and decreased in the contralateral muscle. The action of the coxo-subalar muscle on the wing stroke is discussed.
The function of gonopodial parts and behavioral pattern during copulation by Gambusia (Poeciliidae)
Authors: Peden Alex E.
Published: August 2008

Through the use of movie film and artificial female models, the position of the pectoral fin and the manner in which gonopodial parts are used during copulation by male Gambusia were investigated. The evidence suggests that before gonopodial thrust and copulation, the gonopodium is folded, positioned below the pectoral fin, and twisted with gonopodial ray 3 rotating beneath ray 5. This permits the spines of ray 3 to face laterally and the elbow of ray 4a to project upward and possibly contact or even in some cases lock with the pectoral fin. During gonopodial thrust, males of all 14 species of Gambusia which were studied were observed on occasion to rotate their body until they faced head to tail with females and models. This body rotation is in a direction that helps to maintain the direction of twist and folding of the gonopodium.
Drift of invertebrates in an intermittent stream draining marshy terrain of west-central Alberta
Authors: Clifford Hugh F.
Published: August 2008

Seven 24-h drift samples were taken with a plankton net (pore size: 76 μ) over a 1-year period from an intermittent stream that drains marshy, muskeg-type terrain of west-central Alberta, Canada. The drift was mainly composed of planktonic and benthic animals originating in the marsh. The only abundant lotic taxon in the drift was simuliid larvae. Rotifers and cyclopoid nauplii were numerically the most important taxa. Drift densities for the fauna as a whole tended to decrease as the ice-free season progressed, but there was no consistent correlation between drift densities and flow. However total daily drift across a point varied directly with flow. All the abundant taxa drifted more during the day than at night, and nematodes, harpacticoids, simuliid larvae, chironomid larvae, chydorids, and rotifers were found in significantly (P < 0.05) greater numbers in the daytime drift. Drift rates of taxa caught in the plankton net were compared with drift rates of the same taxa caught in a 320-μ drift net. Rotifers, entomostracans (especially the immature stages), and even small simuliid and chironomid larvae would have been seriously underestimated using only the 320-μ net. The marshy areas via drift through the intermittent tributaries contribute a very large number of small organisms to the main stream. Draining the wetlands might have a pronounced detrimental effect on the main stream's ecosystem.
Light alteration caused by snow and its importance to subnivean rodents
Authors: Evernden L. N. , Fuller W. A.
Published: August 2008

Silicon photocells placed in three habitats before snowfall revealed that light levels in the subnivean environment are inversely related to thickness of snow cover. Under 15 cm of snow in the fall, detectable light was sharply reduced. Under midwinter snow depths of 30 to 50 cm no light was detectable by the photocells used and color temperature readings showed greatest penetration to ground level in the red end of the visible spectrum. Sexual maturation of laboratory females of Clethrionomys gapperi was stimulated by white and blue radiation and increased daylength during late winter. Red light was not stimulatory, even over a 16-h day. As in other mammalian species, male voles did not appear to be as strongly photosensitive as females. Captive voles, given a choice of lights of different wavelength and total darkness, exhibited light-avoidance. Thus, the physiological and behavioral reactions of voles to the modified subnivean light regime ensure that subnivean winter breeding does not occur in this species. Factors controlling maturation of microtines that do breed under snow ought to be investigated.
The biology of Gammarus (Crustacea, Amphipoda) in the northwestern Atlantic. VI. Gammarus tigrinus Sexton
Authors: Steele D. H. , Steele V. J.
Published: August 2008

Gammarus tigrinus is an endemic estuarine species of the northwestern Atlantic found from the St. Lawrence estuary south to Florida. At St. Andrews, N.B., 50% maturity occurs at 6.1 mm in the female. Females produce a series of broods between April and September at which time they enter the resting stage. The oogonia begin to enlarge in February, but are not fertilized until April. The young hatched in the spring probably enter the resting stage in late summer before producing the first brood. The older generation disappears in the summer and the life cycle is annual.
Faunal provinces in Canada as exemplified by mammals and birds: a mathematical consideration
Authors: Kaiser Gary W. , Lefkovitch Leonard P. , Howden Henry F.
Published: August 2008

Although different regions have a characteristic fauna, mathematical techniques based on rates of change in composition, changes in species density, and similarity of composition do not give unequivocal definitions of faunal provinces. There is some concordance between species consistency of large taxonomic groups (mammals, passerine, and non-passerine birds) and the ecological pressures exerted on the groups. Changes in species composition are characterized by gradual shifts over large zones of transition and not by sharp breaks between close homogeneous areas, so that no provinces or divisions are clearly defined.
Antigenicity of the mouse blastocyst
Authors: James D. A. , Yoshida S. M.
Published: August 2008

It has been shown that development of mouse blastocysts, transplanted to ectopic sites in mice, can be inhibited by preimmunizing the host against transplantation antigens of the donor strain. Similar inhibition can be produced by repeated transplants of blastocysts to extrauterine sites in one host. The present investigation reports findings on the nature of this inhibition. Histological examination of recipient organs from hosts presensitized with either transplantation antigens or blastocysts reveals that the principal effect in both cases is upon trophoblast differentiation and proliferation. This effect is subsequently reflected in the size of the haemorrhagic nodule produced in the host organ. Transplantation immunity appears more effective in this respect than blastocyst-elicited sensitivity. It is concluded that trophoblast expresses weak histocompatibility antigenicity and that an immune response of some kind can be elicited by ectopically situated blastocysts. The immunological factor responsible for the observed progressive diminution of growth has not been determined but does not appear to be cell mediated.
Hygroreceptors of adult sawtoothed grain beetles, Oryzaephilus surinamensis (L.) (Coleoptera, Cucujidae)
Authors: Arbogast Richard T. , Roppel Richard M. , Carthon Margaret
Published: August 2008

Two types of sense organs are present on the antennae of adult sawtoothed grain beetles, Oryzaephilus surinamensis. Sensilla chaetica are present on all the antennal segments and sensilla basiconica are present on the three segments which compose the antennal club. The intensity of the beetles' humidity response was correlated with the number of sensilla basiconica remaining after amputation of various numbers of antennal segments. On the basis of their morphology and the results of the amputation experiments, it is concluded that at least some of the sensilla basiconica function in hygroreception.
Rate of accumulation of chlorinated hydrocarbon pesticide residues in adipose tissue of mink
Authors: Aulerich R. J. , Ringer R. K. , Polin D.
Published: August 2008

Dieldrin, DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane), and DDD (1,1-dichloro-2,2-bis(p-chlorophenyl)ethane) were fed to mink to ascertain the rate of accumulation and isomeric distribution of the residues in adipose tissue. Activated carbon was incorporated into the rations in an attempt to reduce the rate of pesticide residue accumulation. Adipose tissue samples, procured biweekly by biopsy, were analyzed by gas chromatography for pesticide residues.Mink fed 100 ppm DDT plus 50 ppm DDD had tissue pesticide levels averaging 373 ppm by the 2nd week of feeding and 510 ppm by the 4th week. Control tissues averaged from 5 to 23 ppm DDT and its isomers. In control tissues, the three isomers DDT, DDD, and DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethane) accounted for 59, 15, and 26%, respectively, of the total concentration. In samples from treated mink, the relative concentration of DDT, DDD, and DDE was 74, 23, and 3%, respectively, of the total level. The dieldrin content of tissues from mink fed 2.5 ppm dieldrin plateaued at about 21 ppm in 4 weeks.Activated carbon in the diet at 4410 ppm did not influence the rate of pesticide accumulation in the fat, the level at which the pesticide residues tended to plateau, or the distribution of DDT and its isomers.
Scanning electron microscopy of the pit of the maxillary palp of selected species of Culicoides
Authors: Rowley Wayne A. , Cornford Marcia
Published: August 2008

The pits on the third segment of the maxillary palps of Culicoides variipennis, C. obsoletus, C. crepuscularis, C. haematopotus, and C. guttipennis were studied with the scanning electron microscope. The size and shape of the palpal pits and the type and number of sensilla were determined for females of each species and for males of C. variipennis and C. crepuscularis. The bulb-shaped sensilla are remarkably similar in all species, but there are considerable interspecific differences in the size of the pits and in the number of sensilla. The two species that normally feed on large mammals (C. obsoletus and C. variipennis) have significantly fewer sensilla per pit than do species considered ornithophilic. Also, males have fewer sensilla than do females of the same species.
Development of thermoregulation in ducklings
Authors: Untergasser G. , Hayward J. S.
Published: August 2008

The embryos of mallards and scaups show no evidence of homeothermy before the point of hatching. The ability to thermoregulate develops quickly directly after hatching, so that day-old mallards remain homeothermic for at least 2.5 h at ambient temperatures down to +2 °C. The lowest ambient temperatures at which 1-day-old scaups and common eiders remain homeothermic for at least 2.5 h are −2 °C and −7 °C respectively. This rapid development of cold resistance is related to increases in peak metabolic rates and insulative capacities. In embryos of pipped eggs, metabolic rates do not exceed 1.1 ml O2/g h for mallards and 1.6 ml/g h for scaups, while the peak metabolic rates of the day-old young are 6.1 and 7.0 ml/g h respectively. One-day-old common eiders have a peak metabolic rate of about 5 ml/g h. After an age of 3 days, cold resistance increases with age while peak metabolic rates decrease, indicating that reduced heat loss contributes to increased cold resistance. At an age of 7 days, mallards can maintain homeothermy for at least 2.5 h at −4 °C, scaups at −14 °C, and common eiders at −16 °C. Insulation indices of eider ducklings are significantly higher than those of young mallards and scaups.
Functional micromorphology and circadian growth of the rock-boring clam Penitella penita
Authors: Evans J. W. , LeMessurier Marie H.
Published: August 2008

Ground sections, acetate peels, and scanning electron microscopy are used to visualize the microstructure and fine growth lines of the shells of Penitella penita, collected from different substrates. Growth increments of approximately daily duration were found in the area of the umbonal ventral sulcus. Two morphologically different types of growth increments are described, those deposited during the period of quiescence and growth (7 to 10 days) and those deposited during the succeeding period of active boring (5 to 8 days). The duration of a full cycle of growth and boring varies considerably, but averages 15 days.The width of growth increments and the microstructure of the shell is controlled by the amount of space within the burrow, and this in turn depends primarily on the substrate hardness. The effect of other factors, such as disturbance, and tidal and seasonal fluctuations, is minor by comparison.The microstructure of juveniles differs from that of older animals and the number of lines per group is reduced.
The composition and metabolism of fatty acids in Ips paraconfusus Lanier (Coleoptera: Scolytidae)
Authors: Penner K. R. , Barlow J. S.
Published: August 2008

The fatty acid composition of newly emerged Ips paraconfusus Lanier shows no sexual dimorphism and is approximately as follows: C14:0, 0.5%; C16:0, 23.0%; C16:1, 6%; C18:0, 3%; C18:1, 55%; C18:2, 9%; C18:3, 2%. Both sexes, but particularly the female, use up fatty acids, particularly the monounsaturated acids, during reproduction. Isotope from 1-14C-acetate injected into newly emerged females appeared in all saturated and monounsaturated fatty acids within 30 min. There was evidence of de novo synthesis of C14:0 and C16:0, chain elongation of C16:0 to C18:0, and desaturation of C16:0 and C18:0 to yield C16:1 and C18:1 respectively.
Monogenetic trematodes from the Bay of Quinte area, Ontario. IV. Genus Dactylogyrus Diesing, 1850, with provisional host–parasite and parasite–host lists
Authors: Hanek George , Fernando C. H.
Published: August 2008

In this fourth and final paper on the monogenetic trematodes from the Bay of Quinte area, Ontario, the genus Dactylogyrus Diesing, 1850 is studied. Host–parasite and the parasite–host lists of the monogenetic trematodes recovered during the entire survey are presented.
Ovarian development of Melanoplus sanguinipes (Fab.) (Acrididae: Orthoptera) in relation to utilization of water-soluble food proteins
Authors: Krishna S. S. , Thorsteinson A. J.
Published: August 2008

Virgin, 7- to 10-day-old adult Melanoplus sanguinipes (Fab.) were fed on leaves of different plant species or on bran. Water-soluble prsoteins and amino acids in the hemolymph, ovary, or faeces were compared by disc electrophoresis, colorimetry, and thin-layer chromatography. The data were interpreted in terms of quantity and quality of the food proteins and in relation to developmental rate and survival.
The harp seal, Pagophilus groenlandicus (Erxleben, 1777). XXI. The structure of the vestibular apparatus
Authors: Ramprashad F. , Money K. E. , Ronald K.
Published: August 2008

The structure of the large vestibular apparatus of the harp seal (Pagophilus groenlandicus) is similar to that of other mammals. However, the posterior semicircular canal is the smallest of the three canals and the plane of the lateral is below that of the posterior semicircular canal. An additional sensory end organ (crista neglecta) is present about 0.75 mm from the posterior crista. The neuroepithelium of the crista neglecta is similar to that of the crista of the semicircular canals and consists of large supporting and sensory cells, the sensory hairs of which project into the cupula. No otoconia were seen on the crista neglecta as were present on the otolithic membrane of the maculae utriculi and sacculi. A large macula utriculi and crista neglecta may be necessary for body orientation during diving.
The ruby laser as an instrument for cutting the stylets of feeding aphids
Authors: Barlow C. A. , McCully Margaret E.
Published: August 2008

A method is described by which a ruby laser is used to sever the stylet bundles of feeding aphids. This technique insures that the stylets remain in situ in the plant tissue during cutting.
Henneguya sp. (Sporozoa: Myxosporida) as a probable cause of death of Esox niger in Brome Lake, Québec
Authors: Delisle Claude E.
Published: August 2008

Fantham et al. had studied and proposed H. esocis in 1939. Since that time, no other study has been carried out on this subject. The parasite described was also found in Brome Lake chain pickerel and caused a gill filament infection as described by Fantham et al. However, the morphology of the parasite is somewhat different than H. esocis and moreover, the infection is serious enough to be the probable cause of death of the hosts. All specimens autopsied were found heavily infected by Henneguya sp.
Morphology and histology of the endocrine glands of Zootermopsis angusticollis Hagen (Isoptera)
Authors: Gillott Cedric , Yin Chih-Ming
Published: August 2008

The morphology and histology of the endocrine glands of the various castes of Zootermopsis angmticollis were examined. Six types of median neurosecretory cells are distinguishable by size and stain affinity. No differences in the relative numbers of these cell types among castes can be seen. It is postulated that they may be different forms of the same cell during its synthetic and secretory cycle. Lateral neurosecretory cells can be identified consistently only in mature primary reproductives of both sexes. In the corpora cardiaca two types of cells occur; the fuchsinophilic cells are distributed generally whereas the cells that take up counterstain are restricted to the center of the gland. Intercellular neurosecretory cell product is found throughout the gland. No histological changes associated with the formation of particular castes were observed. The corpora allata (CA) vary in size and histological appearance according to caste but not sex. The CA of reproductives (primary and supplementary) and presoldiers are larger than those of juveniles of the same instar; those of soldiers are about the same size as those of the corresponding juvenile stage. These size increases are due mainly to changes in the ratio cytoplasmic diameter: nuclear diameter of the constituent cells and not to an increase in cell number. The H-shaped molt glands, which, as in other pterygote insects, disappear within a few days of the imaginal molt, are composed of a large prothoracic portion and a smaller cephalic ('ventral gland') portion extending anteriorly and dorsally. Histologically the two components are indistinguishable. Running through the glands are thin strands of muscle.
Etude de trois populations de Viviparus malleatus (Reeve) (Gastropoda, Prosobranchia) de la région de Montréal. II. Etude qualitative et quantitative de la nourriture
Authors: Stanczykowska Anna , Plinski Marcin , Magnin Etienne
Published: August 2008

The contents of the digestive tracts of specimens of Viviparus malleatus were estimated quantitatively by a volumetric method and qualitatively by using the ratio algae/other elements present. Types of algae used by these specimens were also determined. Qualitative and quantitative variations in food habits were studied in relation to size, sex, and degree of maturity of individuals, and also with habitat and seasons of the year. The quantity of food available seems to affect the population density while food quality affects growth, fecundity, and production.
Temporal and spatial patterns of allele and genotype frequencies at the Ng locus in blue grouse (Dendragapus obscurus)
Authors: Redfield J. A. , Zwickel F. C. , Bendell J. F. , Bergerud A. T.
Published: August 2008

The frequency of alleles and genotypes at the Ng locus in blue grouse from nine populations on Vancouver Island and the adjacent mainland was examined in an effort to detect systematic variations. There were no significant variations in allele frequencies between populations. Three of the nine populations sampled had significant departures from Hardy-Weinberg equilibrium conditions. Samples of four different cohorts indicated no significant shifts in allele or genotype frequencies between cohorts. These data, combined with other observations, suggest that the alleles at this locus are being maintained by selection. Thus, the utility of this locus as a marker in population studies is strengthened.
Diurnal periodicity in peripheral parasitemias in ducklings (Anas boschas) infected with Leucocytozoon simondi Mathis and Leger
Authors: Roller N. F. , Desser S. S.
Published: August 2008

The peripheral parasitemias of 19 naturally infected ducklings were determined at 2-h intervals from 0800 h of one day through 0800 h of the next day. A diurnal periodicity in parasitemia of L. simondi was clearly established, and was characterized by peak, densities during the daylight hours, and relatively low numbers of gametocytes at night. Gametocytes were localized in the liver, but not in the heart, when the peripheral parasitemias were low. Explanations for the diurnal fluctuations in parasitemia are advanced. The most prominent feeding period of the vector, Simulium rugglesi, coincided with the period of elevated parasitemia in the avian host.
Temperature dependence of tissue metabolism in monotremes
Authors: Aleksiuk Michael , Baldwin John
Published: August 2008

The oxygen consumption of liver and skeletal muscle homogenates from the platypus (Ornithorhynchus anatinus) and the echidna (Tachyglossus aculeatus) was measured over the range 5° to 40 °C. Tissue metabolism in all cases bears an exponential relationship to temperature, with Q10 values ranging from 1.9 to 3.4.
Echinococcus multilocularis in the cotton rat. The effect of preexisting subcutaneous cysts on the development of a subsequent intraperitoneal inoculum of protoscolices
Authors: Rau M. E. , Tanner C. E.
Published: August 2008

Cotton rats were inoculated subcutaneousîy with small cysts of Echinococcus multilocularis and challenged intraperitoneally with 100 protoscolices 40 days later. Subcutaneous cysts which attained weights of more than about 5 g effectively suppressed the establishment, growth, and transperitoneal dissemination of the challenging infection. Normal cotton rats, inoculated intraperitoneally with 100 protoscolices, characteristically developed massive cysts which weighed, on the average, 31 g and consisted of about 31 cyst clusters. In contrast, animals which already harbored large, subcutaneous cysts developed only very mild infections following intraperitoneal reinoculation. Such hosts supported never more than two small, intraperitoneal cysts with a mean total weight of less than 1 g. The intensity of this suppression was underscored by the fact that even a single protoscolex or a small vesicle of E. multilocularis inoculated intraperitoneally into normal cotton rats could give rise to 11 g of cyst material distributed among as many as 87 cyst clusters.
Concerning some littoral Cladocera from Avalon Peninsula, Newfoundland
Authors: Smirnov N. N. , Davis Charles C.
Published: August 2008

Samples were obtained in the littoral region of six small waters in the eastern portion of the Avalon Peninsula, Newfoundland. The Cladocera encountered in the collections are listed. Of the 13 species and varieties that were identified, 10 are new for the island of Newfoundland, 8 are new for the Province of Newfoundland and Labrador, and 5 are new for Canada. Acroperus alonoides Hudendorff and Graptoleberis testudinaria occidentalis Sars have not previously been identified from North America.
Site selection by parasitic helminths: interspecific interactions, site segregation, and their importance to the development of helminth communities
Authors: Holmes John C.
Published: August 2008

That parasites actively select specific sites in their hosts is well known. Some parasites respond to changing conditions within the host by making diel or other short-term migrations, which may be modified by the presence of other parasites.Evidence is presented to support the hypothesis that continued interactions between parasites lead to niche diversification, and that site segregation, and consequently narrow site specificity, is an important part of niche specialization. The paucity of cases of interactive site segregation as compared with those of genetically stabilized selective site segregation suggests that parasite faunas are mature communities, the diversity of which has been established to an important extent through biotic interactions.
Photoperiodism in Orthopodomyia signifera
Authors: Bradshaw William E.
Published: August 2008

Larvae of the tree-hole mosquito, Orthopodomyia signifera, were collected from North Carolina and subjected to long- and short-day photoperiods. Long days at 25 °C permit rapid molting of fourth instar larvae to pupae. Lower temperature (15 °C) modifies developmental rate but does not appear to block photoperiodic response to long days. Short days at 25 °C may halt development, may retard development, or may permit rapid development in either the third or fourth larval instar. O. signifera is probably polymorphic for both the stage at which diapause may occur and for the depth or firmness with which it is established.
Hydroptila eramosa a new caddis fly from Southern Ontario (Trichoptera, Hydroptilidae)
Authors: Harper P. P.
Published: August 2008

The adult male of Hydroptila eramosa n. sp. is described from Southern Ontario and is briefly compared with other similar species of the "waubesiana group."
A description of intraerythrocytic schizonts and gametocytes of a haemogregarine of the snapping turtle Chelydra serpentina
Authors: Desser Sherwin S.
Published: August 2008

Examination of blood from 37 snapping turtles (Chelydra serpentina) from Algonquin Park, Ontario, revealed that all harbored haemogregarine gametocytes. Only after prolonged examination of thin blood films was schizogony observed within erythrocytes of two turtles. Mature schizonts contained six merozoites. The number of merozoites and the scarcity of schizonts are discussed in relation to haemogregarines of other cheloneans, as well as of teleosts and elasmobranchs.
The fine structure of the cecal epithelium of Megalodiscus temperatus
Authors: Morris Gerald P.
Published: August 2008

The cecal epithelium of Megalodiscus temperatus (Stafford 1905) contains two cell types. Although the major component of the epithelium is a syncytium there are also isolated, small, mononucleate cells located in the basal region. The mononucleate cells are always in contact with the underlying basal lamina and show no signs of secretory activity. The lumenal surface is extended in the form of numerous long, closely packed, cylindrical microvilli with tapering tips. Each microvillus may be up to 25 μ long and possesses a central fibrillar core. The cytoplasm of the cecal syncytium contains numerous Golgi complexes which produce membrane-delimited granules containing a dense, homogeneous matrix. These granules appear to be releasing their contents either at the lumenal surface or immediately beneath it. The base of the cecal syncytium but not that of the mononucleate cell type is penetrated by numerous projections of underlying muscle cells. No evidence of endocytotic activity by the cecum can be detected by incubation in thorium dioxide.
The intranuclear occurrence and fine structural details of schizonts of Perezia fumiferanae (Microsporida: Nosematidae) in cells of Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae)
Authors: Percys Jean
Published: August 2008

Perezia fumiferanae (Microsporida: Nosematidae), a parasite of Choristoneura fumiferana (Lepidoptera: Tortricidae), occurs within several tissues of the host. Schizonts occur within both nucleus and cytoplasm and are separated from the host only by their own membrane. The ultrastructure of the schizonts supports the suggestion that P. fumiferanae is a member of the genus Nosema.
The first known female of the African long-eared bat Laephotis wintoni (Vespertilionidae: Chiroptera)
Authors: Peterson R. L.
Published: August 2008

A subadult Laephotis wintoni Thomas taken west of Mount Kenya in Kenya on 22 June, 1972, represents the fourth specimen and the first known female of that taxon. Measurements are compared with those of three males, and systematic relations within the genus are discussed. The soft palate is illustrated for the first time.
Notes on the captive wolf (Canis lupus) colony, Barrow, Alaska
Authors: Lentfer Jack W. , Sanders Don K.
Published: August 2008

The Naval Arctic Research Laboratory wolf colony at Barrow, Alaska, originated from 15 pups taken shortly after birth from dens near Anaktuvuk Pass, Alaska. Controlled breeding has resulted in 17 litters. Minimum breeding age for both sexes is 22 months. Maximum observed but not established breeding age for a Barrow colony female is 7 years and for a male is 9 years. An Anchorage, Alaska, zoo female wolf had young at 9 years. Birth dates extend from 19 May to 7 June. Rivalries, especially among females, increase just before the breeding season. Original breeding stock have passed their predominantly dark coloration to offspring.
Parental calls and the approach behavior of young Canada geese: a laboratory study
Authors: Cowan P. J.
Published: August 2008

A laboratory experiment was conducted to test whether parental calls of the Canada goose, calls A, B, and C, each recorded from a different individual goose, differentially affect the approach behavior of call A experienced and parental call naive goslings. Experience before with call A produced a greater number of approach responses to this call relative to the other calls and a parental call of the ring-billed gull. After training with a call, in the experiment paired with visual movement, individual parental calls can have distinct effects on the approach behavior of goslings. This process involving auditory and visual elements may be the basis of individual recognition in the Canada goose.
Yolk deposition in the Douglas-fir bark beetle, Dendroctonus pseudotsugae (Hopk.): the significance of physiological state of oocytes
Authors: Sahota T. S. , Ibaraki A.
Published: August 2008

In vitro yolk deposition was studied in ovaries dissected out of Dendroctonus pseudotsugae at various times after attack on host logs, and incubated in medium containing a mixture of labeled haemolymph and ovarial proteins. These proteins were not deposited in the oocytes taken from beetles which had been on host logs for less than 48 h. Such proteins were deposited as yolk in the basal and penultimate oocytes from beetles which had been on host logs for more than 48 h; younger oocytes from the same ovaries did not exhibit yolk deposition. Presence of juvenile hormone in the incubating medium did not induce yolk deposition in oocytes not already engaged in vitellogenesis.
The cryostat: a tool for the big game biologist
Authors: Child Kenneth N.
Published: August 2008

A relatively rapid and simple cryostat method developed to process incisor teeth of Columbian black-tailed deer (Odocoileus hemionus columbianus, Richardson) for analysis in age-determination studies is described. The simplicity of the sectioning technique promises the method broad applicability in studies attempting to establish objective age characteristics within large mammal populations.
Heart rate during breath-holding and diving in the unrestrained harbor seal (Phoca vitulina richardi)
Authors: Jones David R. , Fisher H. Dean , McTaggart Susan , West Nigel H.
Published: August 2008

Heart rate and breathing movements have been monitored in three unrestrained harbor seals. On voluntary submergence heart rate fell markedly in all seals, and after 2–3 s submergence stabilized at about 40–50% of the predive level. Heart rate increased before the animals broke surface at the end of the dive and, when breathing began again, a postdive tachycardia was observed. Two of the three seals frequently showed anticipation of the dive as judged from their heart-rate response. Heart rate during feeding dives was generally more variable; in fact one seal exhibited no bradycardia in 20% of its feeding dives, although another seal showed a significantly greater bradycardia than was seen in routine dives. When breathing rate was low (less than five breaths min−1) respiratory variations in the heart rate occurred, although the onset of bradycardia was much more rapid during diving than during breath-holding. Because of the flexibility of the response it is concluded that the generation of diving bradycardia in the seal is a complex phenomenon which, aside from any responses set in train by peripheral receptors, must also involve some form of associative learning.
Some aspects of the biology of Calliopius laeviusculus (Krøyer) (Crustacea, Amphipoda) in the northwestern Atlantic
Authors: Steele D. H. , Steele V. J.
Published: August 2008

Calliopius laeviusculus is an amphiboreal species found on rocky shores in the western Atlantic from Hudson Bay south to Long Island Sound. Fifty percent of the females were calculated to be mature at 5.6 and 6.7 mm in the summer and winter respectively in Newfoundland waters, but, in Labrador, maturity was not achieved in females up to 10 mm in length. In Newfoundland several generations are produced per year and the females may have more than one brood. However, the females are in the resting stage between August and November–December and young are only released from spring until late summer. The overwintering animals are larger than those found in the summer and the population reaches a peak in late summer. In Labrador, where only one generation is produced per year, young are released in the spring but probably do not reach maturity until the autumn. In Newfoundland fecundity does not vary seasonally.
Paragymnophallus odhneri gen. n., sp. n. (Trematoda: Gymnophallidae) for Gymnophallus somateriae sensu Odhner (1900, 1905)
Authors: Ching Hilda Lei
Published: August 2008

Odhner's specimens of Gymnophallus somateriae were studied and are assigned to a new genus and new species because of the wide genital pore located between the ventral sucker and the intestinal bifurcation. Paragymnophallus odhneri also differs from G. somateriae as described by Levinsen (1881) and Ching (1973), in the body spination, 2:1 sucker ratio, nature of the vitellaria, and the egg size. G. somateriae reported by Ryzhikov et al. (1966) from Somateria spectabilis in Chutkova is considered to be P. odhneri because of the checkerboard arrangement of spines, 2:1 sucker ratio, and small eggs. Pending reexamination of the genital pore, G. bilis Brinkmann, 1956 and G. minor Ryzhikov, 1962 could belong to Paragymnophallus. The new genus, most similar to Gymnophallus in the bipartite seminal vesicle, follicular vitelline glands, and Y-shaped excretory bladder, differs in the location and size of the genital pore, larger sucker ratio, and large pharynx. The wide genital pore some distance from the ventral sucker and the large oral sucker are like that of Parvatrema but Parvatrema has a club-shaped seminal vesicle, minute body, compact vitellaria, and V-shaped excretory bladder. A key to the genera of Gymnophallidae is included.
Adaptation to cold: energy metabolism in an atypical lagomorph, the arctic hare (Lepus arcticus)
Authors: Wang Lawrence C. H. , Jones Douglas L. , MacArthur Robert A. , Fuller William A.
Published: August 2008

Unlike other lagomorphs or any other mammals living in a cold environment, the basal metabolic rate of the arctic hare, Lepus arcticus monstrabilis (0.36 cm3 O2/g per hour) was only 62–83% of the values predicted from its body weight. The minimum thermal conductance (0.010 cm3 O2/g per hour per degree centigrade) was also reduced to only 51–59% of its weight-specific value (0.019–0.017 cm3 O2/g per hour per degree centigrade). The normal body temperature (38.9C), however, was comparable to that of other lagomorphs. The daily energy consumption between ambient temperatures of −24 and 12.5C was between 262 and 133 kcal, which is 6–43% above the minimum resting values at corresponding ambient temperatures.It is concluded that the reduction of surface area to volume ratio and the effectiveness of its insulation are sufficient compensations so that the arctic hare can maintain a normal body temperature with a depressed basal metabolic rate. Such a reduction of metabolism is energetically adaptive for a species living exclusively in a cold and relatively barren habitat.
Cardiofilaria pavlovskyi Strom, 1937 and Avioserpens sp. (Nematoda) from Canadian ciconiiform birds
Authors: Gibson George G.
Published: August 2008

Cardiofilaria ardae (Mawson, 1957) is considered to be a synonym of Cardiofilaria pavlovskyi Strom, 1937, specimens of which were found in Ardea herodias from New Brunswick and in a new host, Ixobrychus exilis, from Ontario. Male and immature female Avioserpens sp. are reported from Botaurus lentiginosus, Quebec, and immature females from I. exilis, Ontario. The males have six to seven caudal papillae per side and have spicules that resemble those of A. mosgovoyi Supryaga, 1965 but are nearly twice as long. The status of the seven nominal species of Avioserpens is discussed briefly.
Spruce budworm moth trapping using virgin females
Authors: Miller C. A. , McDougall G. A.
Published: August 2008

A grid of 25 traps baited with virgin female moths was used to monitor the abundance of male spruce budworm in relatively sparse populations for 12 successive years. Concurrent sampling of third-instar larvae showed that the male moth counts of one generation had a predictive relationship to third-instar larval counts of the next generation and therefore the sex-attractant trap is a feasible means of measuring budworm abundance at low population densities. But three sampling constraints must be noted: (a) a moth invasion will generally invalidate the relationship;(b)extrapolation of a moth–larvae relationship observed in one forest biotype to biotypes with different host characteristics is risky; (c) the probability of a female attracting a particular male decreases sharply with increasing population density.Trapping success is discussed with respect to location and height within the stand and to weather conditions.
Identification of the somata of common inhibitory motoneurons in the metathoracic ganglion of the cockroach
Authors: Pearson K. G. , Fourtner C. R.
Published: August 2008

The somata of the three common inhibitory neurons known to innervate many muscles of the metathoracic legs of the cockroach have been identified by allowing cobalt chloride to diffuse up the cut axons of these cells and by precipitating the cobalt with ammonium sulfide. The black precipitate of cobalt sulfide allowed the somata and axonal pathways of these three cells to be clearly visualized. All three somata are located near the midline on the ventral surface of the ganglion. The most posterior of these somata is just contralateral and sends branches directly out lateral nerves 3, 4, and 6, and indirectly into nerve 5 via a small connective between nerves 4 and 5. The other two somata each send a branch out only nerve 5. The somata of the fast and slow excitatory motor axons to the coxal depressor muscles were also identified in this study.
Analysis of copepod heart rates using Arrhenius plots
Authors: Borgmann Uwe
Published: August 2008

A comparison of the Arrhenius plots of the heart rate of 43 individual copepods (Euchaeta japonica), collected from two different areas, indicates a consistency in slope, but the heights may vary. It is hypothesized that, when differences in slope do occur, these may reflect differences in the genetic and (or) physiological state of the organisms and could be used to characterize animals in a similar way that electrophoresis is now used.
Ultimate upper lethal temperature of Atlantic salmon Salmo salar L.
Authors: Garside E. T.
Published: August 2008

Parr (70–147 mm) of Atlantic salmon Salmo salar L. from Big Brook, Terra Nova National Park, Newfoundland, were progressively acclimated to 27.5C in fresh water of the home stream, and the upper lethal temperature was determined by probit analysis to be 27.80C ± 0.41. This is essentially the ultimate upper lethal temperature.
Changes in the visual pigments of trout
Authors: Allen Donald M. , McFarland William N. , Munz Frederick W. , Poston Hugh A.
Published: August 2008

The proportions of two visual pigments (rhodopsin and porphyropsin) were examined in four species of trout under experimental and natural conditions. Brook trout (Salvelinus fontinalis), rainbow trout (Salmo gairdneri), and brown trout (Salmo trutta) have different relative proportions of visual pigments in their retinae. The visual pigment balance in wild cutthroat trout (Salmo clarki) is related to forest canopy (access to light) and season. The brown trout have a more red-sensitive and less labile pair of visual pigments than brook or rainbow trout, which respond to photic conditions by increasing the proportion of porphyropsin (in light) and increasing rhodopsin (in darkness). The brown trout have a high percentage of porphyropsin, regardless of experimental conditions. This result does not reflect an inability to form rhodopsin but rather may relate to a consistently high proportion of 3-dehydroretinol in the pigment epithelium. The possible advantages and mechanisms of environmental control of trout visual pigment absorbance, as currently understood, are discussed.