bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on the eyes of toadfishes Opsanus. Structure and reflectivity of the stratum argenteum
Authors: Nicol J. A. C.
Published: December 2009

The light-adapted eye of the toadfish (Opsanus, Batrachoididae) exhibits eyeshine. The chorioid is yellow and has a yellow stratum argenteum. This is a bilaminate tissue, consisting of an inner iridescent sheet containing pentagonal crystals, and an outer sheet containing birefringent yellow granules. There is no melanocyte layer in the chorioid. In the photopic eye the retinal pigment migrates into the cell processes and surrounds the cone outer segments. Spaces between the cones and processes are pigment free, and part of the light incident upon the retina is transmitted through it to the argenteum and reflected by the latter into the retina. The pertinent tissues are illustrated, and spectrum curves for transmission and reflection are presented.
Vie larvaire des ouaouarons Rana catesbeiana Shaw (Amphibia Anura) des Laurentides, Québec
Authors: Bruneau Marcel , Magnin Etienne
Published: December 2009

The 8908 tadpoles of Rana catesbeiana used in this study come from three lakes of the Laurentian region, north of Montreal (45°52′ N, 74° W). Histograms of body length and various morphometric data taken on the subjects revealed a few aspects of their biology. The majority of tadpoles undergo metamorphosis after two winters, and the remainder, in variable number according to the years, after three winters. Body length is approximately 4 mm 10 to 15days after spawning; it varies between 19 and 26 mm after the first winter, between 40 and 52 mm after the second winter, and between 53 and 56 mm after the third. The largest tadpole had a body length of 68 mm and a total length of 162 mm. Growth occurs mostly in June, July, and August and it varies with temperature. Metamorphosis never occurs before a tadpole reaches a body length of 43 mm, a total length of 100 mm, and has posterior legs of 50 mm in length. This usually happens in July or at the beginning of August. The tadpoles that are about to undergo metamorphosis seem to look for the warmest spots of the lake.
Seasonal parasitic infections in mooneye, Hiodon tergisus (LeSueur), from the Assiniboine River
Authors: Glenn C. L.
Published: December 2009

Four species of parasites were found in certain organs and tissues of 367 mooneye collected from the Assiniboine River during a 12-month period. One specimen of the acanthocephalan Pomphorhynchus bulbocolli was noted in each of two mooneye. Over 85% of all mooneye aged I–VIII were infected with the nematode Cystidicoloides tenuissima and (or) the flukes Paurorhynchus hiodontis and Crepidostomum hiodontos. Incidence of infection in "young-of-the-year" was lower (45–74%) and no young fish netted in June had parasites. Abundance of C. tenuissima and P. hiodontis in infected fish varied from peaks in summer to lows in winter. Maximum numbers of C. hiodontos occurred during winter. Cystidicoloides tenuissima and C. hiodontos were located primarily in the gut, but P. hiodontis was widely spread throughout the body tissues.
The epicuticle of a marine isopod, Idotea baltica (Pallas)
Authors: Halcrow K.
Published: December 2009

An unusually elaborate epicuticle is described in Idotea baltica. The bulk of the epicuticle consists of a central tightly packed array of irregularly cylindrical cavities arranged perpendicularly within an electron-dense matrix. The latter is continuous with material composing a layer on each side of the central layer. The outermost layer contains vesicles the lumina of which are seen frequently to open to the outside. Similar vesicles are seen within the central layer, and at the junction of this layer and the innermost layer of the epicuticle. The latter is the narrowest of the three regions and bears abundant small projections where it contacts the outermost region of the exocuticle.
Activity of breeding Peromyscus leucopus
Authors: Harland Richard M. , Millar John S.
Published: December 2009

Activity of lactating and nonbreeding Peromyscus leucopus was examined under seminatural conditions. Lactating females spent significantly more time away from the nest (307 min/night) than nonbreeding females (173 min/night). Increased time away from the nest was related to an increased duration of each activity bout rather than the number of bouts. Lactating and non-breeding females also showed different responses to meteorological conditions. Time away from the nest by lactating females was not significantly related to litter size or age of litter. The significance of these trends to breeding females and their offspring is discussed.
Further studies on the biology of the banded woollybear, Pyrrharctia (Isia) isabella (J. E. Smith) (Lepidoptera: Arctiidae). IV. Diapause development as influenced by temperature
Authors: Goettel Mark S. , Philogène Bernard J. R.
Published: December 2009

The banded woollybear, Pyrrharctia (Isia) isabella (J. E. Smith), was reared from egg to larval diapause at 22, 26, and 30 °C. Field-collected and laboratory-reared larvae were weighed twice weekly and kept at different temperatures (0, 5, 10, 22, 26, and 30 °C). The larvae reared at 22 and 26 °C were found to remain viable at 5 °C, whereas those reared at 30 °C were not. Chilling was not an absolute requirement for diapause development, although mortality was high at higher temperatures. Temperature is critical in the maintenance of weight and for survival of diapausing larvae. Other factors than diapause seem to be involved in cold hardening.
Avian Haemoproteidae. 14. The haemoproteids of the avian family Rallidae
Authors: Bennett Gordon F.
Published: December 2009

The haemoproteids of the avian family Rallidae are reviewed. Haemoproteus porzanae Galli-Valerio, 1907 and H. gallinulae de Mello, 1935, are redescribed; H. fulicae da Fonseca, 1938 is declared a synonym of H. gallinulae. Haemoproteid records from the Rallidae are summarized.
Thermal niche overlap in garter snakes (Thamnophis) on Vancouver Island
Authors: Gregory Patrick T. , McIntosh A. G. Duncan
Published: December 2009

Although the three species of garter snakes (Thamnophis) on Vancouver Island have generally different diets, they overlap in food habits to some extent. Consequently, additional separation along other niche dimensions is expected. In this study, differences in thermal niches were examined in the field. Two of the three species had similar body temperatures and both were significantly different from the third. The linear relationship between body and substrate temperatures was not statistically different among species, however, allowing body temperatures to be directly related to habitat and (or) activity period differences. Extremes of habitat selection, rather than differences in diel activity periods, probably account for most of the interspecific variation in body temperature. On the other hand, the three species do coexist in some habitats and the observed differences in mean body temperature are small. Body temperature also varied slightly according to sex and reproductive condition, gravid females generally being warmer than other snakes.
Description, relationships, and host symptoms of Ditylenchus dryadis n.sp. (Nematoda: Tylenchidae) from the Canadian High Arctic, a transitional species of gall-forming parasite attacking Dryas integrifolia M. Vahl
Authors: Anderson R. V. , Mulvey R. H.
Published: December 2009

Morphology and symptoms of Ditylenchus dryadis n.sp., a bisexual leaf galling parasite that is similar taxonomically to D. dipsaci and pathogenically to the Anguininae, are described and illustrated. The main differentiating characters for the female are its large, distended postuterine sac, which occupies 75% of the vulva–anus distance and the quadricolumellate crustaformaria; and, for both sexes, six to eight incisures, presence of a conspicuous deirid, a basal esophageal bulb of three cells that does not overlap the intestine, and an acute tail terminus. Disease symptoms are galls of various configurations on the leaves only of Dryas integrifolia M. Vahl, ecologically the most important of the vascular plants from the type locality and a new host record for plant parasitic nematodes. Galls examined on dried leaves were typically red, had diameters of up to 5 mm, and contained from 2 to 60 nematodes with numerous eggs.
Population size, variability, and aggregation among forest lepidoptera in southern Ontario
Authors: Dean John M. , Ricklefs Robert E.
Published: December 2009

Abundance, variability, and aggregation of larval populations of 162 species of lepidoptera, feeding on the foliage of primarily deciduous trees in southern Ontario, were analyzed to test four hypotheses about the relationship of species to their resources. The lepidoptera larvae were treated both as exploiters of foliage and as resources for parasitoids. Multiple regression and partial correlation analysis revealed that (1) the abundance and variability of a moth population were independent of the diversity of host trees fed upon, (2) the incidence of parasitism on a moth population was independent of the variability of the host population, and (3) the diversity of parasites of a moth was independent of the variability of the host population. We raise the possibility that parasites may be ineffective control agents for lepidoptera species.
Shift in cell type of newt iris epithelial cells in culture
Authors: Zalik Sara E. , Dimitrov Eva
Published: December 2009

Cell suspensions obtained from dorsal irises of newts of the species Notophthalmus viridescens were grown under conditions of cell culture. The ability of these cells to give rise to lens-protein-producing cells was determined using fluorescent antibodies. After 42 days of culture depigmented cell clusters appeared which stained specifically with lens antibodies. Cell aggregates positive for lens crystallins were evident until 84 days of culture. Although cell aggregates were present in cultures maintained for 98 days, they did not stain with lens antibodies. It is concluded that a shift in the differentiation route can occur in iris cells under these conditions but that the aggregation of depigmented cells into clusters may not always be associated with the synthesis of lens specific proteins.
Reproduction and nutrient reserves of arctic ground squirrels
Authors: Kiell David J. , Millar John S.
Published: December 2009

Body composition, caloric value, and size of selected organs of arctic ground squirrels (Spermorphilus parryii) were examined seasonally and in relation to reproductive status in order to determine if females obtain nutrients for offspring from stored reserves prior to the availability of new vegetation. Seasonal changes in body composition were similar in males and females. Females showed a depletion of skeletal components, total fat, and caloric value during lactation. The mean reduction in caloric value between pregnancy and lactation (495 kcal; 1 cal = 4.1868 J) accounted for only 31% of the estimated 1600 kcal contributed to offspring by a female. Females must support offspring through an increased ingestion of food prior to the availability of new vegetation.
Guanine in strata argentea of fish eyes
Authors: Nicol J. A. C.
Published: December 2009

Guanine was found to be the main component in extracts of argentea of redfish Sciaenops ocellata (Sciaenidae) and chorioids of sheepshead Archosargus probatocephalus (Sparidae). The argenteum of the redfish contained 1.55 mg guanine/cm2 surface area of chorioid. Hypoxanthine content was about [Formula: see text] that of guanine. The purines occurred as bisymmetrical hexagonal crystals ranging in shape from needles to platelets.
Evidence for permanent population differences in the annual cycle of plasma "antifreeze" levels of winter flounder
Authors: Fletcher G. L. , Smith J. C.
Published: December 2009

Seasonal changes in plasma freezing point depression and Cl− concentration in a population of Nova Scotian winter flounder were compared with the seasonal changes which occurred in a population of Newfoundland flounder. The plasma protein "antifreeze" component of the freezing point depression was computed by subtracting the freezing point depression due to the concentration of plasma electrolytes from the total plasma freezing point depression.In Nova Scotian flounder the plasma "antifreeze" level increased approximately 1 month later and declined 2 months earlier than it did in Newfoundland flounder. These differences between the two populations of fish correlated with the regional differences in seawater temperature.When Nova Scotian flounder were transferred to Newfoundland and maintained under Newfoundland conditions of water temperature and photoperiod they retained their plasma "antifreeze" cycle for the duration of the study (approximately 1 year).These results suggest that the timing of the annual plasma "antifreeze" cycle may be a permanent feature of the flounder's physiology and that water temperature does not directly control it. It is hypothesized that some aspects of the annual antifreeze cycle may be endogenous and that if photoperiod plays a role in its regulation the differences between Newfoundland and Nova Scotia are too slight for the cycle to be adjusted in 1 year.
Postnuptial molt of the song sparrow on Mandarte Island in relation to breeding
Authors: Dhondt André A. , Smith James N. M.
Published: December 2009

In the summer of 1978 we made 133 captures of 69 adult song sparrows on Mandarte Island, B.C., where the detailed breeding history of all birds was known. Molt condition and weight of all trapped individuals was noted. Molt follows the usual pattern for passerines, but secondary molt does not finish until a few days after primary molt. In the population, molt lasts from June to September, and individual molt takes about 50 days. Both sexes begin molt simultaneously. Birds that stop breeding early molt at the same time as nonbreeding individuals, but late-breeding song sparrows postpone molt. Birds that stop breeding early start molt just before the young become independent. In late breeders, feeding fledglings and molt overlap, with overlap increasing the later breeding ends. Old birds molt later because they tend to breed later and because young birds begin molt sooner after their last young hatch.Body weight increases during molt and decreases after molt, but remains about 1 g heavier than premolt weight. Birds breeding later began molt lighter.We suggest that the molt period on Mandarte is earlier than in other populations because breeding begins earlier and because individuals must finish molting before autumn territorial behaviour begins.
Generation times and reproductive rates of Amoeba proteus (Leidy) as influenced by temperature and food concentration
Authors: Rogerson Andrew
Published: December 2009

Temperature was found to have a marked effect upon the generation times of Amoeba proteus when cultured with Tetrahymena pyriformis at 20, 15, and 10 °C. The length of the cell cycle varied from 44 h at 20 °C to 2926 h at 10 °C. For each temperature studied, generation times followed a U-shaped distribution where the greatest division potential was determined by the prey concentration. Optimum reproductive rates were achieved at lower food levels as temperature was decreased. The results are discussed in the context of the available published literature.
Inhibition of the use of endogenous substrates by Galleria mellonella transacylases
Authors: Barlow J. S. , Jones D.
Published: December 2009

The addition of bovine serum albumin (BSA) to preparations of Galleria mellonella microsomes reduced their ability to acylate L-α-glycerophosphate with endogenous acyl groups. The reduction was 83% at 5 mg BSA/mL and 90% at 20 mg BSA/mL. At the same time, BSA increased acylation with exogenous K-palmitate by 28 and 47% at 5 and 20 mg BSA/mL respectively. At 10 mg BSA/mL and optimum K-palmitate concentrations (3 mM), acylation of endogenous substrates is reduced to about 3% of the total acylation. Under these conditions, measurements of enzyme specificity for various exogenous acyl substrates are more meaningful.It is suggested that BSA binds to and carries endogenous acyl groups away from the active site of the enzymes on the microsomal membranes while simultaneously carrying in exogenous acyl groups. Measurements of L-α-glycerophosphate incorporation by several preparations of microsomes show considerable variability but offer no clues to its possible causes.
Abnormal weight gain in mice, induced by Trichinella pseudospiralis
Authors: Al Karmi T. O. , Faubert G. M.
Published: December 2009

The parasite-induced weight gain in animals is an unusual phenomenon which involves a complex host–parasite relationship. Trichinella pseudospiralis exhibits such a phenomenon in mice. Eighty Swiss mice were orally infected with 600 T. pseudospiralis or Trichinella spiralis muscle larvae. The total body weight of the mice was recorded at the time of infection and at 2 and 10 months after, and compared with an uninfected control group. Trichinella pseudospiralis muscle larvae induced an abnormal weight gain. This weight increase is statistically different from the other two groups of mice after 2 and 10 months postinfection. The results indicate the existence of a different type of host–parasite relationship between the two parasites. Some speculative ideas are advanced to explain the rapid growth effect of T. pseudospiralis on its host.
Role of volatile and nonvolatile components of Sitka spruce bark as feeding stimulants for Pissodes strobi Peck (Coleoptera: Curculionidae)
Authors: Alfaro R. I. , Pierce Jr. H. D. , Borden J. H. , Oehlschlager A. C.
Published: December 2009

The feeding stimulatory activity on the white pine weevil, Pissodes strobi Peck, of various types of extracts from Sitka spruce, Picea sitchensis (Bong.) Carr., was tested using a paired agar disc bioassay. Chemicals that induce feeding apparently constitute a complex mixture of non-volatile compounds in the phloem and on the surface of the bark and needles. Volatile chemicals from the bark and foliage, captured in Porapak Q, did not attract walking P. strobi in two olfactometers, nor did they trigger a feeding response when tested on plain agar. However, the monoterpenes α-pinene, β-pinene, and β-myrcene acted as synergists to the nonvolatile chemicals in the bark, while piperitone had a marked feeding deterrent effect. (+)-Camphor and limonene stimulated the feeding at low concentrations but caused feeding inhibition when the concentration rose above a particular threshold.
Territorial behaviour by prairie pothole blue-winged teal
Authors: Stewart G. R. , Titman R. D.
Published: December 2009

The territorial behaviour of wild blue-winged teal (Anas discors) was studied in pothole country near Minnedosa, Manitoba, through observation of marked individuals.Aggressive behaviour in the form of threat, rush, and pursuit flight contributed to the establishment and maintenance of blue-winged teal territories. Paired males were intolerant toward all other members of their species. Pursuit flights, which were most successful in expelling intruders from territories, increased dramatically during nest establishment and territory delineation.Territories averaged 0.69 ha and consisted of one or two potholes or portions thereof. They were discrete, well defined areas which remained stable from the time of nest site selection to the 3rd week of incubation.Blue-winged teal territories provide exclusive feeding areas for females where they are free from harassment during the nesting period. The female may thus channel her energy to the production of progeny while her mate protects his genetic investment from attempted rape.
Cell renewal in the gills of the fish Barbus conchonius
Authors: MacKinnon Marlene , Enesco Hildegard E.
Published: December 2009

This radioautographic study established that the epithelial cells of the teleost gill have the cell division and cell migration patterns characteristic of a cell renewal system. [3H]Thymidine was injected into the small tropical fish Barbus conchonius, where it became incorporated into the newly synthesized DNA of dividing cells. Three fish were sacrificed at each of the following postinjection time intervals: 1, 12, 24, and 36 h. At 1 h, labeled nuclei were found only at the base of the gill filament, near the gill arch. At each successive time interval, labeled nuclei were found further out along the length of the gill filament. At later stages, labeled nuclei were also seen at the tips of the lamellae which project perpendicularly from the filaments. The number of labeled nuclei at the point of origin steadily declined with time. These data demonstrate that gill epithelial cells originate at the base of the gill arch and migrate both outward along the filament and upward along the lamellae. This pattern of cell division and cell migration demonstrates that the gill epithelium is a cell renewal system.
Cleidodiscus robustus Mueller, 1934 (Monogenea: Ancyrocephalinae) from Lepomis gibbosus L. (Pisces: Centrarchidae) in Ontario, Canada: anatomy and systematic position
Authors: Beverley-Burton M. , Suriano D. M.
Published: December 2009

Cleidodiscus robustus Mueller, 1934 (Monogenea: Ancyrocephalinae) from the gills of Lepomis gibbosus L. (pumpkinseed) in Ontario, Canada, is redescribed with details of the internal anatomy as well as the sclerotized components of the haptor and copulatory complex. A revised generic diagnosis incorporating features of the reproductive system is presented.
Haplocleidus dispar (Mueller, 1936) and Pterocleidus acer (Mueller, 1936) (Monogenea: Ancyrocephalinae) from Lepomis gibbosus L. (Pisces: Centrarchidae) in Ontario, Canada: anatomy and systematic position
Authors: Beverley-Burton M. , Suriano D. M.
Published: December 2009

Haplocleidus dispar (Mueller, 1936) Mueller, 1937 and Pterocleidus acer (Mueller, 1936) Mueller, 1937 (Monogenea: Ancyrocephalinae) from the gills of Lepomis gibbosus L. (pumpkin-seed) in Ontario, Canada, are redescribed with details of their internal anatomy as well as the sclerotized components of the haptor and copulatory complex. Revised generic diagnoses incorporating features of the reproductive systems are presented.
Temporal aspects of juvenile pink salmon (Oncorhynchus gorbuscha Walbaum) emergence from a simulated gravel redd
Authors: Godin Jean-Guy J.
Published: December 2009

The temporal pattern and daily timing of sibling pink salmon fry emerging from a simulated gravel redd were examined in the laboratory under a 12 h light: 12 h dark cycle and at temperatures ranging from 3.4 to 15.0 °C. The distribution of sibling fry emergence was generally unimodal in time, but differed significantly from normality. The rate of emergence decreased as temperature increased, owing in part to a positive relationship between the duration of the emergence period and mean temperature. Timing of 50% emergence was correlated negatively with mean temperature. Emergence was mainly nocturnal at all temperatures except 15.0 °C. However, the fry's tendency to emerge during daylight increased progressively during the course of the emergence period for all redds except the one at 5.0 °C. The onset of darkness appeared to be the major time cue for emergence at temperatures ≤ 12.3 °C. In general, the daily peak of fry emergence occurred within 3 h after the onset of darkness.
Ontogenetic changes in the daily rhythms of swimming activity and of vertical distribution in juvenile pink salmon (Oncorhynchus gorbuscha Walbaum)
Authors: Godin Jean-Guy J.
Published: December 2009

Pink salmon fry exhibited, on the average, an irregular daily pattern of swimming activity, and swam near the water surface at night (nocturnal rhythm of vertical distribution) during the 1st week after gravel emergence. The nocturnal rhythm of vertical distribution indicated a relative negative response of the fry to high light intensities. A shift from an irregular pattern to a diurnal rhythm of swimming activity occurred 7 to 13 day s after emergence. Coincident with this shift was an increasing tendency of the fry to swim in the upper half of the water column during daylight. This suggested a gradual weakening of the fry's negative phototactic response during the 2nd week. Thereafter, daily rhythms of swimming activity were diurnal, whereas rhythms of vertical distribution remained nocturnal. Periodogram analysis revealed that these behavioural rhythms were synchronized strongly with the artificial, daily light–dark cycle. The onset of light appeared to synchronize the diurnal swimming activity rhythms, whereas the onset of darkness synchronized the nocturnal patterns of fish rising toward the water surface.
New records and extensions of range of reptant decapod Crustacea from the northeastern Pacific Ocean
Authors: Hart Josephine F. L.
Published: December 2009

New distribution records for 13 species of reptant decapod Crustacea are reported. Calocaris investigatoris, Calastacus stilirostris, Hapalogaster grebnitzkii, Mursia gaudichaudii, and Oregonia bifurca are new to the waters off British Columbia and Pagurus hemphilli, P. quaylei, and Discorsopagurus schmitti are new to Alaska. Callianassa gigas, Pachycheles pubescens, Petrolisthes cinctipes, Scleroplax granulata, and Pagurus caurinus have been found farther north than previous published records. It has been determined that Hapalogaster grebnitzkii has not been found in California and that the southernmost known record is northern British Columbia.
Stable swimming by diagonal phase synchrony in arthropods
Authors: Barr David , Smith Bruce P.
Published: December 2009

The aquatic mite, Limnochares americana Ldbld., in common with several types of insects which are also secondary invaders of fresh water, can swim only by stroking the legs on opposite sides of successive segments in phase (diagonal phase synchrony). A planar model developed to analyse the distribution of forces generated during this type of swimming demonstrates that there is a substantial potential for lateral instability (yaw) inherent in the locomotory pattern. The model also suggests morphological adaptations that could minimize the instability. Substitution of measured variables for L. americana and for the beetle Hydrophilus piceus in the model indicate that, consistent with observations, the mite has been considerably more successful than the beetle in minimizing lateral instability. It is concluded that diagonal phase synchrony represents an ancestral coordination pattern which is less efficient than the more derived method of coordination by transverse phase synchrony.
Vascular pathways in the gill of ling cod, Ophiodon elongatus
Authors: Farrell A. P.
Published: December 2009

Corrosion plastic casts were made of the gill vasculature in ling cod (Ophiodon elongatus) using methyl methacrylate. The vessels afferent and efferent to the gills are described, as well as the microvasculature of the filament. There is a respiratory network and a venolymphatic network. The venolymphatic network is derived from efferent arteries and thus all cardiac output must pass through the gill lamellae.
Gill morphometrics, vessel dimensions, and vascular resistance in ling cod, Ophiodon elongatus
Authors: Farrell A. P.
Published: December 2009

The morphology, morphometric relationships, and vascular geometry were established for ling cod gills using fixed tissue and vascular casts. Calculations using Poiseuillian and sheet flow equations permitted predictions of the resistance and the pressure drop in various vessels of the respiratory network in the gill filament. It was found that the afferent lamellar arteriole was the major vascular resistance. Blood transit times through the gills were also calculated and discussed.
Structural and functional aspects of tail squirting: a unique defense mechanism of Diplodactylus (Reptilia: Gekkonidae)
Authors: Rosenberg Herbert I. , Russell Anthony P.
Published: December 2009

The structure of a unique caudal gland is described for the first time. Glandular material is secreted and stored in a series of caudal chambers that makes up the bulk of the tail. The glandular secretion is forcibly ejected from each chamber through a middorsal rupture zone in the epidermis. Localized contraction of caudal musculature causes ejection of the defensive secretion.All species of Diplodactylus that were known or suspected to be tail squirters plus representatives from each of four other species groups were examined. The following species of Diplodactylus have caudal glands: D. ciliaris, D. elderi, D. michaelseni, D. spinigerus, D. strophurus, D. taenicauda, and D. williamsi.Regenerated tails of gland-bearing species contain a regenerated caudal gland which is structurally different from the original. Here all evidence of segmentation is lost and there is no series of epidermal rupture zones. A pair of elongated secretion masses is found within paired, elongated caudal chambers.The results of a preliminary bioassay indicated that caudal gland secretion may be unpalatable to potential predators and thereby protects the species of Diplodactylus that are tail squirters. The very sticky nature of the secretion may complement the repellant effects of the odorous constituents.
The population ecology of the leech (Hirudinoidea:Glossiphoniidae) Theromyzon tessulatum
Authors: Wilkialis Jozef , Davies Ronald W.
Published: December 2009

In northeast Poland approximately 50% of lentic and lotic sites sampled contained Theromyzon tessulatum. The seasonal pattern of changes in population structure was similar in both lentic and lotic sites. Breeding occurred between June through August when the new generation of young appeared in the field population. The overwintering population consisted of young-of-the-year and immature individuals produced the preceding summer, but which had not bred. The time taken for an individual to attain maturity was dependent on the number and frequency of the blood meals taken. A minimum of three full blood meals was required to reach maturity. The timing of these meals and the intervals between them determined whether breeding occurred when the leeches were approximately 12 or 24 months old.
The population ecology of the leech (Hirudinoidea:Glossiphoniidae) Theromyzon rude
Authors: Davies Ronald W. , Wilkialis Jozef
Published: December 2009

The seasonal pattern of changes in population structure of Theromyzon rude in Alberta shows a breeding period extending from May through September. Young first appear in the field population in July and continue to form a large proportion of the population through October. A seasonal migration into the shallow water zone during the ice-free period and from the shallow water zone into the deep water zone during the period of ice cover was determined.
Ion-stimulated ATPase activity and NaCl uptake in the gills of freshwater mussels
Authors: Dietz Thomas H. , Findley A. M.
Published: December 2009

Microsomal membranes prepared from gills of the freshwater mussel Carunculina texasensis contain HCO3− ATPase, Cl−–HCO3− ATPase, and Na+–K+ ATPase activity. The HCO3− ATPase activity displays saturation kinetics with a Vmax of approximately 10 μM P/mg protein∙h−1 and an affinity of 5 mM HCO3−. The HCO3− ATPase can be stimulated by the addition of 1 mM Cl−, but it is inhibited by > 3 mM Cl− and by SCN−. The gill tissue ouabain-sensitive Na+–K+ ATPase activity represents approximately 1.5 μM P/mg protein∙h−1, which is low compared with the Mg2+ ATPase activity (12 μM P/mg protein∙h−1). We present preliminary evidence that the gills in freshwater mussels are a major site of Na+ and Cl− accumulation.
Are (some) biological heat or cold sensors electrolytic thermocouples?
Authors: Wright R. H.
Published: December 2009

Electrolytic thermocouples provide a plausible operating mechanism for the heat and cold sensors of insects. The purpose of this note is to suggest the sort of structures to be looked for in the detailed anatomy of the sensillae.
Influence of photoperiod on growth in Baltic salmon parr (Salmo salar L.) with special reference to the effect of precocious sexual maturation
Authors: Lundqvist Hans
Published: December 2009

Individually tagged 2-summer-old Baltic salmon parr (Salmo salar L.) from Ume River (63°50′ N, 20°05′ E), Sweden, were exposed to photoperiods of either 6 h light – 18 h dark (LD 6:18) or 20 h light – 4 h dark (LD 20:4) during autumn. Fish subjected to natural day length (nLD) served as controls. Sexually immature female and male fish exposed to LD 20:4 grew more rapidly than salmon exposed to LD 6:18 and natural photoperiod. Sexually maturing male parr subjected to LD 20:4 grew more slowly than immature fish in the same photoperiod and did not differ significantly in growth rate compared with maturing males in LD 6:18 and nLD.Precocious male parr subjected to LD 6:18 and nLD became ripe in the middle of October while mature fish in LD 20:4 exhibited a delay in the ripening.It is suggested that either the major androgen 11-ketotestosterone, or gonadotropin (GTH), or both, inhibit photoperiod-stimulated growth in precocious males.
Effects of sex steroids on plasma lipids in the goldfish, Carassius auratus
Authors: Wiegand Murray D. , Peter R. E.
Published: December 2009

The effects of sex steroids on plasma lipids in female goldfish were studied in sexually regressed and maturing fish at 12 °C, and in recent postovulatory-regressed fish at 21 °C. Intraperitoneal injection of oestrone (E1), but not oestradiol (E2), raised plasma triglyceride (TG) concentrations in regressed fish, but oestrogen had no effect on plasma TG in either maturing fish at 12 °C or in recent postovulatory–regressed fish at 21 °C. Progesterone injection caused high levels of plasma TG in maturing fish at 12 °C. Fish injected with E1or E2 had higher plasma total cholesterol (TC) levels posttreatment compared with control fish in both experiments at 12 °C, but E1 and E2 were without effect on plasma TC at 21 °C. Both E1 and E2 raised plasma lipid phosphorus levels in all three experiments. Testosterone generally had little effect on plasma lipids. These results support the hypothesis that oestrogen is involved in lipid mobilization in teleosts, and it appears that this effect is sensitive to warm temperature. There was no support for a mammalian-like, progesterone-stimulated system for clearance of plasma TG in the female goldfish.
Distribution, morphology, and taxonomy of the psychrolutid fish Cottunculus granulosus (Karrer) from the southwestern Atlantic
Authors: Nelson Joseph S. , Nakamura Izumi
Published: December 2009

Cottunculus granulosus, previously known only from the holotype, is now known to be relatively common and to occur from Uruguay to southernmost Argentina at depths of 150–1250 m as a result of trawling expeditions by the Federal Republic of Germany, Japan, and United States. Two forms exist, a plain-colored, short-spined form and a banded, long-spined form. It is possible that Bunocottus apus represents the same species as C. granulosus. Of the six or so species of Cottunculus, C. granulosus appears to be most closely related to C. microps, C. sadko, and C. thompsoni of the North Atlantic and Arctic oceans.
Sexual recognition and anticuckoldry behaviour in savannah sparrows
Authors: Weatherhead Patrick J. , Robertson Raleigh J.
Published: December 2009

Models of male and female savannah sparrows were presented 179 times in 11 territories through the breeding season. Detection of the models was highly temperature dependent. Using only trials in which the models were detected it was found that before nest initiation both models were treated as male, whereas during the early nesting period the male model was treated as male and the female model was treated as female. Later in the nesting period both models were treated as female although the female elicited stronger responses. These results are interpreted as consistent with predicted anticuckoldry behaviour by breeding males.
Temporal spacing of broods, brood size, and parental care in song sparrows (Melospiza melodia)
Authors: Smith James N. M. , Roff Derek A.
Published: December 2009

This study examines temporal spacing between successive broods of song sparrows on Mandarte Island, British Columbia, Canada. In 1977 and 1978 brood spacing was strongly influenced by the size of the earlier brood. In 1978 only, pairs with more nesting experience were able to renest sooner. Song sparrow females did not begin to incubate a later clutch while caring for more than one fledged young. Triple-brooded females took less time on average from fledging earlier broods to beginning subsequent ones and raised more young per season than females breeding twice.Although large broods delay renesting, a simple model shows that the extra time required to raise large broods does not influence the optimal brood size in Mandarte Island song sparrows. A similar model for the great tit (Parus major) suggests that season length may influence optimal brood size in this species.Clutch size in Mandarte Island song sparrows does not vary consistently within seasons or among years. Reproductive success was uniform for the first two-thirds of the breeding season, but late nests produced few independent young. Clutches of four eggs were most common and produced more young on average than did clutches of three.
The relationships between ambient oxygen concentration, temperature, body weight, and oxygen consumption for Mysis relicta (Malacostraca: Mysidacea)
Authors: Sandeman I. M. , Lasenby D. C.
Published: December 2009

The relationships between ambient oxygen concentration, temperature, body weight, and oxygen consumption for Mysis relicta in Kootenay Lake, B.C. are examined. Mysis oxygen consumption rate declined with both decreasing temperatures and ambient oxygen concentrations.
Two species of Grania (Oligochaeta, Enchytraeidae) from the Pacific Coast of North America
Authors: Coates Kathryn , Erséus Christer
Published: December 2009

Grania paucispina (Eisen, 1904) and Grania incerta sp.nov. are described, both found in marine sands of California and British Columbia. The species are closely related. Their setae are morphologically very similar, and they both have small glands at their spermathecal openings which distinguish them from other species of the genus. They differ from each other primarily in the distribution of the setae and in body appearance.
Active respiration rates for the burrowing wolf spider Geolycosa domifex (Hancock)
Authors: McQueen Donald J.
Published: December 2009

The locomotion of individual burrowing wolf spiders, Geolycosa domifex (Hancock), was continuously monitored over 24-h periods and at the same lime respiration rates (microlitres CO2) were also continuously recorded. Five categories of activity and rest were identified: (1) in-burrow activity, (2) surface activity, (3) vertical activity, (4) in-burrow rest, and (5) surface rest. Respiration rates were determined for each category with respect to spider weight and temperature. The vertical activity rates were 10 times higher than resting rates, the surface activity rates were 4.5 times higher, and the in-burrow activity rates were 3.2 times higher. The activity–respiration rates were combined in a simple model which was tested against independently collected data and found to be in agreement. Scope for activity was calculated with respect to both weight and temperature, and it was found that the smallest animals at the lowest temperatures had the greatest scope for activity expressed as microlitres CO2 per gram body weight.
Coexistence of three species of hawks (Buteo spp.) in the prairie–parkland ecotone
Authors: Schmutz J. K. , Schmutz S. M. , Boag D. A.
Published: December 2009

We investigated the extent of ecological segregation in the use of the food, space, and habitat resources of three sympatric species of the genus Buteo (red-tailed, ferruginous, and Swainson's hawks) coexisting in the prairie–parkland ecotone of southeastern Alberta. We concluded that food was not a resource for which the hawks were competing because the overlap in diets exceeded 80%, and because ferruginous hawks successfully fledged supernumerary broods and Swainson's hawks, broods of at least average size. Furthermore, there was no evidence that each species hunted prey at different times of the day or concentrated on different-sized prey. Each of the three species exhibited a dispersed distribution of nest sites which suggests competition for space; this pattern was not as evident when the distribution of nests among species was considered. Nevertheless, when pairs of different species nested in close proximity their reproductive success declined significantly, suggesting interspecific competion for space. The three species exhibited differences in nest site characteristics, suggesting that, although sympatric, they tended to segregate on the basis of habitat. Ferruginous hawks appear to inhabit arid and open landscapes, red-tailed hawks woodland habitat, and Swainson's hawks the interface.
Description of some larval shortnose sturgeon (Acipenser brevirostrum) from the Holyoke Pool, Connecticut River, Massachusetts, U.S.A., and the Saint John River, New Brunswick, Canada
Authors: Taubert Bruce D. , Dadswell Michael J.
Published: December 2009

Shortnose sturgeon (Acipenser brevirostrum) protolarvae, ranging from 8.0 to 12.5 mm TL, had 20–23 postanal and 33–36 preanal myomeres and the preanal length was 66–70% of TL. The yolk sac was large, the pectoral fin buds were barely visible, and the entire body was covered with expanded melanophores. Mesolarvae of 13.0–14.7 mm TL had 22 postanal and 34 preanal myomeres, and preanal length was 61% of TL. The yoke sac was nearly gone, barbels, mouth, and pectoral fins were well developed and the anlage of the dorsal fin was visible. Mouth width of the 14.7 mm TL mesolarva was 71% of the head width and teeth were present.
Movement patterns and foraging ecology of a stream caddisfly larva
Authors: Hart David D. , Resh Vincent H.
Published: December 2009

The movement patterns and time–activity budgets of Dicosmoecus gilvipes were quantified from underwater observations of marked individuals in a northern California stream, during two studies in early and late June, 1977. Individuals traveled several metres per day. The only striking differences between the observed patterns of movement and those predicted from a random walk model are the following: (a) in both studies, large larvae moved significantly farther than small larvae; (b) in both studies, there is a pronounced diel rhythm to movement, with animals traveling faster during the day; (c) rates of travel in late June are ~3 times faster than those in early June. Since more than two-thirds of the total time–activity budget of these larval insects is dedicated to feeding, we suggest that the patterns of movement reported here largely reflect activities related to food acquisition. Several observations indicate that food is locally limiting and heterogeneously distributed across the stream bottom, thus requiring animals to move from patch to patch in order to meet their food requirements. Seasonal differences in rates of movement appear to result from phenological changes in the quantitative and qualitative food requirements of these stream insect grazers.
Mechanisms of fine particle capture by larval black flies (Diptera: Simuliidae)
Authors: Ross Douglas H. , Craig Douglas A.
Published: December 2009

Larval black flies remove fine particulate matter from stream water using a mucosubstance which coats their filtering organs (cephalic fans). This mechanism, common among filter feeding marine invertebrates, but not previously reported in freshwater insects, explains how simuliids capture fine particles (0.091 – ca. 30 μm) which would otherwise escape the cephalic fans. Investigations of two theoretical filter feeding models revealed that direct interception is probably the predominant mode of fine particle filtration for black flies. The ability of simuliids to capture fine particles, which are abundant in many streams and often support a rich nutritive microflora, may account in part for their occurrence and success in diverse lotic habitats.
Ultrastructure de I'érythrocyte du triton Pleurodeles waltlii Michah
Authors: Sean K. E. , Lassalle B. , Boilly B.
Published: December 2009

The erythrocytes of the newt Pleurodeles wultlii Michah are characterized by the presence of DAB negative cytoplasmic autophagic-type vacuoles; these vacuoles have an intense acid phosphatase activity and are expelled by exocytosis. Golgi, rough endoplasmic reticulum, and mitochondria ate not well developed and generally present an altered form; the nucleus is characterized by condensed chromatin without pseudoperoxidase activity. These results suggest that the erythrocyte of Pleurodeles seems to have a low metabolism and to partly mature in the circulating blood.
Food habits of two Vancouver Island wolf packs: a preliminary study
Authors: Scott B. M. V. , Shackleton D. M.
Published: December 2009

The food habits of two packs of Vancouver Island wolves were studied between February and November 1978. Analysis of guard hairs in 616 scats showed that the major food of these wolves was black-tailed deer, Roosevelt elk, and beaver, respectively. Seasonal variation in the wolves' use of these three prey species and of different age-classes of ungulates were found. Composition of scats from den and rendezvous sites were significantly different from scats collected during equivalent periods along logging road and trails.
Range extensions, new distribution sites, and notes on the biology of sacoglossan opisthobranchs (Mollusca: Gastropoda) in British Columbia
Authors: Millen Sandra V.
Published: December 2009

Northern ranges of six species of sacoglossan gastropods are extended into British Columbia. New distribution sites and observations on food, habitat, and spawning are included for the following eight species: Alderia modesta, Aplysiopsis smithi, Elysia hedgpethi, Hermaea oliviae, Hermaea vancouverensis, Olea hansineensis, Placida dendritica, and Stiliger fuscovittata.
New records of nematodes in the house crow (Corvus splendens Vieillot) in Asia
Authors: Wong P. L. , Poon S. K. , Anderson Roy C.
Published: December 2009

Cardiofilaria pawlowskyi Strom, 1937 and Diplotriaena tridens (Molin, 1958) Boulenger, 1928 are reported for the first time in Corvus spendens Vieillot from Malaysia.
Effects of Truttaedacnitis truttae (Nematoda: Cucullanidae) on growth and swimming of rainbow trout, Salmo gairdneri
Authors: Russell L. R.
Published: December 2009

Growth and swimming abilities of fingerling and 1.5-year-old rainbow trout infected with the nematode parasite Truttaedacnitis truttae were examined. Control trout and trout infected in the laboratory with 5, 10, 20, 40, or 80 worms exhibited similar growth characteristics over a 10-week period within each of four experimental groups fed different rations of trout chow (1, 2, 3, or 4% of wet body weight fed per day). Decreasing growth rates showed some correlation with increasing numbers of nematode parasites. Differences between growth rates, amounts of food consumed, and food conversion efficiencies of infected and noninfected fish were not statistically significant. Critical swimming speed, fixed velocity, and burst velocity stamina tests revealed similar swimming abilities in both control and infected trout. Maximum swimming speeds attained and time to fatigue at cruising speeds were more closely related to fish size than to numbers of worms with which fish were infected. Importance to rainbow trout survival of large natural infections with T. truttae is discussed.