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1.
  • 1.1. A high percentage (53%) of isolated snails injected with prostate gland homogenates lay eggs.
  • 2.2. These egg masses consist of a few eggs which contain many nonviable oocytes.
  • 3.3. Preliminary experiments suggest that an egg-laying factor may be present in prostatic secretions.
  • 4.4. Snails bred in isolation from hatching, whether injected or not, occasionally lay viable eggs.
  • 5.5. This observation shows that self-fertilization or parthenogenesis is, in fact, possible in Helix aspersa Müller.
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2.
  • 1.1. Fatty acid and lipid class composition were determined in larvae of four marine species: Atlantic halibut (Hippoglossus hippoglossus L.), plaice (Pleuronectes platessa), cod (Gadus morhua) and turbot (Scophthalmus maximus) at hatching and prior to first feeding.
  • 2.2. Total fatty acid content decreased in the four species with up to 50% reduction in one of the halibut groups. Docosahexanaoic acid (22:6 n-3) was especially utilized.
  • 3.3. Low lipid utilization was found in turbot in relation to the other three species.
  • 4.4. Water environmental temperature may explain some of the differences in the fatty acid utilization and the source of metabolic energy between cold water species (halibut, cod, and plaice) and temperate species (turbot), in the period from hatching to prior to first feeding.
  • 5.5. Relative amounts of neutral lipids and phospholipids were similar in plaice, cod and halibut, approximately 25% and 75% of total lipids, respectively, and were approximately constant during the yolk-sac stage. Neutral lipids were dominant for turbot at hatching, accounting for 53–55% of the total lipids, while phospholipids predominated prior to first feeding, being 56–59%.
  • 6.6. Phosphatidylcholine was catabolized in halibut, plaice and cod but not in turbot, while phosphatidylethanolamine tended to be synthesized in all four species.
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3.
  • 1.1. Larvae (first zoeae) of Palaemonetes vulgaris are relatively stenohaline (optimum salinity = 20%.), adults euryhaline (96-hr LD50 values: 0.8 and 51%.).
  • 2.2. The concentration of blood sodium remains nearly constant over the salinity range 5–45%.
  • 3.3. Adult P. vulgaris are less tolerant of dilute (1–20%.) media than sympatric P. pugio but equally tolerant of higher salinities (35–45%.). Palaemonetes vulgaris maintains a slightly more constant and higher (average) sodium concentration in the blood than P. pugio.
  • 4.4. It is suggested that these differences contribute to habitat partitioning of these species and that they reflect the greater affinity of P. vulgaris for a euhaline milieu.
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4.
  • 1.1. Developing eggs of whitefish (Coregonus lavaretus L.) and vendace (Coregonus albula L.) were kept at 1–2°C and some eggs taken gradually up to 8°C to provoke mass hatching of embryos.
  • 2.2. Wet weight, dry matter and the contents of lipid, protein and ash were measured in fish during the course of experiment.
  • 3.3. Dry matter content decreased gradually in whitefish eggs from 15.64 to 11.95% during 1 month at 1–2°C, whereas vendace eggs showed only a slight decrease from 16.27 to 15.53%.
  • 4.4. In both species protein content decreased but lipid increased when approaching the natural time of hatching.
  • 5.5. During delayed hatching at low water temperatures protein contributes to catabolism, whereas lipid content decreased only in the later phase of the experiment.
  • 6.6. Larvae starved for 10 days after hatching lost increasing amounts of dry matter (from 26.1 to 50.3% of body weight) and protein (from 18.7 to 45.9% of body weight) as they remained longer in cold water as embryos.
  • 7.7. A correspondence was found between assessment of metabolic utilization of body stores based on chemical analysis of fish body and previous work on oxygen consumption and nitrogen excretion.
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5.
  • 1.1.The behavioural responses of two species of freshwater pulmonate snails Bulinus (P.) globosus and Bulinus rohlfsi] to sugar gradients were investigated by means of diffusion olfactometers.
  • 2.2.Both snail species proved to be very discriminating in their responses. Of the 17 sugars tested, 35.3%, namely d(−)glucuronic, maltotriose, maltose, cellobiose, d(−)arabinose, d(+)mannose proved to be statistically significant attractants or arrestants to B. rohlfsi. Only 23.5% of these sugars (maltotriose, maltose), d(+) mannose and d(+) xylose were significant attraetants or arrestants to B. (P.) globosus.
  • 3.3.Glucuronic acid was a significant repellent to B. rohlfsi but none of the sugars was a repellent to B. (P.) globosus.
  • 4.4.The results are compared with those obtained for other snail species and their relevance to the ecology and control of the snails are discussed.
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6.
  • 1.1. The Dufour gland secretions of Formica fusca consist mainly of saturated straight and branched chain hydrocarbons (C9–C19), one unsaturated hydrocarbon (C13) and two sesquiterpenoids, farnesene and homofarnesene.
  • 2.2. In F. lemani, the Dufour gland contains branched, saturated and unsaturated hydrocarbons (C9–C19) and two farnesenes.
  • 3.3. The two species were distinguished chiefly by the presence of a relatively large proportion of farnesene in F. fusca, with very little homofarnesene and by contrast, little farnesene but much more homofarnesene in F. lemani.
  • 4.4. The contents of the Dufour gland can be used as a chemotaxonomic clue to distinguish between the species.
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7.
o
  1. 1.The Root effect was measured in hemolysates from representatives of 56 genera of Amazonianfishes.
  2. 2.Hemolysates from several species of air-breathing fishes were found to have Root effects, contraryto published hypotheses.
  3. 3.Hemolysates from Potamotrygon, a freshwater ray, exhibit a Root effect under our experimental conditions.
  4. 4.The pattern of Root effect distribution correlates positively with the distribution of choroid retiamirabile and swimbladders, but not with the distribution of swimbladder retia mirabile; it is proposed that the former is the more primitive structure which is associated with the origin of Root effect hemoglobins
  5. 5.Some of the fish hemoglobins differ spectrally from one another. The positions of the absorptionmaxima of the deoxyhemoglobins range from 553 nm (Lepidosiren paradoxa and Potamotrygon sp.) to 560 nm (Plagioscion)
  6. 6.Occurrence of Root effects is not correlated with the complexity of the hemoglobin electrophoreticpattern, although several species are found to have multiple hemoglobin systems in which the Root effect is restricted to certain components.
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8.
  • 1.1. The glutathione S-transferases of Megachile rotundata (Fab.) were characterized eletrophoretically and spectrophotometrically.
  • 2.2. Differences were found between sexes with respect to number of isozymes and activity with age.
  • 3.3. Inhibition patterns of chalcone, seven of its synthetic derivatives, flavone, quercetin, and tridiphanediol differed with respect to sex and substrate.
  • 4.4. Comparisons are made with the honey bee, Apis mellifera L.
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9.
  • 1.1. Some aspects of the gas exchange system of a diving lizard, Physignathus lesuewii were studied.
  • 2.2. Breathing patterns were analysed.
  • 3.3. Breathing rate increases logarithmically with temperature and Q10 = 1.8. LogBR = −0.237 + 0.0256 T.
  • 4.4. Gas tensions in lung air and arterial and venous blood were measured. Arterial pH declines with increasing temperature.
  • 5.5. Temperature has a marked effect on oxygen affinity of the blood (ΔH = −10.1 kcal mol). A Bohr effect was also noted.
  • 6.6. CO2 equilibrium curves were drawn.
  • 7.7. The results are considered with a view to anticipating the efficiency of the gas exchange system of this species under conditions of variable temperature and during diving.
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10.
  • 1.1. Rates of evaporative water loss (EWL) were measured in Anolis roquet and A. marmoratus each from three localities which varied in conditions of aridity.
  • 2.2. There were significant interpopulational differences in rates of EWL for both species which correlated with habitat aridity.
  • 3.3. Rates of EWL were significantly lower in A. roquet after 6 weeks acclimation to more xeric conditions, populational differences were still evident.
  • 4.4. Acclimational effects on rates of EWL were 2 to 3 times greater than populational differences.
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11.
  • 1.1. The influence of temperature (14,19, 24°C), salinity (26,32, 38,44%.) and food type (artificial diets: Fryfood, Mytilus, Soya, Yeast, Spirulina) on the respiratory rate of Tisbe holothuriae has been studied.
  • 2.2. Oxygen consumption decreased with decreasing temperature, but with a greater rate at supra- or subnormal salinities.
  • 3.3. Multiple-regression analysis showed the quadratic effect of temperature and the linear effect of salinity to be the more important factors affecting respiration.
  • 4.4. The food type also seems to exert an important effect on oxygen consumption.
  • 5.5. A significant lowering of respiration was observed for all food tested when the animals were starved.
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12.
  • 1.1. The chemistry and function of Dufour's gland secretions of two carpenter bees were studied.
  • 2.2. Dufour's gland of Proxylocopa olivieri, a ground nesting bee, produces long chain hydrocarbons that are utilized to line its brood cells and are mixed with its bee bread.
  • 3.3. Dufour's gland secretion of Xylocopa sulcatipes, on the other hand, is dominated by ethyl eicosanoate and ethyl docosanoate accompanied by the corresponding methyl esters and high boiling hydrocarbons.
  • 4.4. This wood nesting bee apparently does not use Dufour's gland secretion to line its nest.
  • 5.5. The relationship between the respective chemistry and function of Dufour's gland secretion and the nesting ecology of the two bees is discussed.
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13.
  • 1.1. The effect of myo-inositol on the ability of three species of nematodes to survive desiccation has been studied.
  • 2.2. Survival rates obtained from worms treated with an inositol bathing medium were compared with survival rates of worms treated with distilled or tapwater media.
  • 3.3. Highest survival rates were found in those nematodes that were placed in an inositol solution prior to desiccation.
  • 4.4. Tapwater facilitated higher revival rates than did distilled water in both D. dipsaci and D. myceliophagous.
  • 5.5. No such differences were found for A. tritici.
  • 6.6. The results are discussed in relation to the possible mechanisms of protection afforded by the different bathing media.
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14.
  • 1.1. The activity of l-gulonolactone oxidase (EC 1.1.3.8) in livers of 49 species of eutherian mammals varied intraspecifically among individuals; coefficients of variation were 0.2 to 0.4 in many species.
  • 2.2. Differences observed in l-gulonolactone oxidase activity among strains of laboratory rats and domestic rabbits are probably genetically controlled.
  • 3.3. Pronounced sex differences in l-gulonolactone oxidase activity were found in some species, particularly in the genera Peromyscus, Reithrodontomys and Onychomys.
  • 4.4. Mormota monax exhibited seasonal variation in l-gulonolactone oxidase somewhat like that previously observed in Sylvilagus floridanus; no such seasonal variation was found in Sciurus carolinensis.
  • 5.5. Hibernation did not affect l-gulonolactone oxidase activity in Spermophilus tridecemlineatus.
  • 6.6. In four species of rodents, Microtus ochrogaster, Tylomys panamensis, Octodon degus and Sigmodon hispidus, l-gulonolactone oxidase activity was not affected by the level of dietary ascorbate.
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15.
  • 1.1. The utility of biochemical genetic methods of bird identification was investigated for some common species which create a hazard for commercial aviation in Ireland.
  • 2.2. Sixteen enzyme loci were assayed in eight species, using starch gel electrophoresis; three larids, three corvids and two columbids.
  • 3.3. Genera were distinguishable using all but two loci.
  • 4.4. Differences within genera were small, but all species except for the gulls Larus argentatus and L. marinus, could be identified using one or more loci.
  • 5.5. Arising from the success of the method using fresh specimens, a protocol for the electrophoretic identification of traumatized remains of strikes is suggested.
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16.
  • 1.1. A comparative examination of sarcoplasmic proteins of the two nominal European species of angler-fish, Lophius piscatorius and L. budegassa was carried out using isoelectric focusing techniques.
  • 2.2. Two protein bands differing in isoelectric point proved diagnostic for L. budegassa (pI 4.40 and pI 5.75) while a third characterized L. piscatorius (pI 4.65).
  • 3.3. These species-specific protein profiles provide a method of species discrimination independent of morphological criteria.
  • 4.4. Within-species heterogeneity of banding pattern suggested the presence of polymorphic gene loci of potential use in studies of population structure.
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17.
  • 1.1. Analysis of the haemolymph composition of two species of New Zealand wetas gave the following data.
  • 2.2. Both species have a typical composition in terms of the inorganic fraction of the haemolymph, with Hemideina femorata having twice the amount of potassium found in H. maori.
  • 3.3. There were high concentrations of proline, glycine and alanine in both species of weta.
  • 4.4. Other organic fractions of the haemolymph of both species appear to be typical for the class Insecta. The significance of the results are discussed.
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18.
  • 1.1. Muscle proteins from the chelae of six crayfish species and ten species of Uca were compared through disc electrophoresis (split gel technique).
  • 2.2. No intraspecies variation of the electrophoretic pattern was found.
  • 3.3. In interspecies comparisons all components (bands) were weighted individually and specified as ancestral or derived characters.
  • 4.4. In the crayfishes the phylogenetic trees constructed from electrophoretic and classical data were found to be congruent. In Uca some branches of either tree remained undefined. Each tree, however, helped complete the other one.
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19.
  • 1.1. A model for target localization, developed for Squilla mantis, was modified for two other stomatopod species.
  • 2.2. While Squilla live in dim light, Odontodactylus scyllarus live in medium bright and Gonodactylus in extremely bright habitats.
  • 3.3. The critical zones for prey capture, selected by a decision neuron, were identified. These are bifurcated, stretching out for long distances.
  • 4.4. A much more limited critical zone is obtained by introducing a strike command neuron, which receives inputs only from the two central ommatidia in the middle band instead of from all six as does the decision neuron.
  • 5.5. The results correspond to the different behavior patterns in prey capture for the different species.
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20.
  • 1.1. Fifteen values were determined in blood samples from six buzzards (Buteo buteo) and six eagle owls (Bubo bubo) over the 24 hr of the day.
  • 2.2. Glucose, urea, uric acid, triglyceride and calcium values showed diurnal rhythms in both species. Their respective patterns of diurnal variation were compared.
  • 3.3. Phosphorus, cholesterol and cholinesterase levels underwent circadian rhythms only in the buzzards. Albumin/globulin and amylase exhibited diurnal variations exclusively in the eagle owls.
  • 4.4. Glutamatic oxaloacetic transaminase, albumin, globulin, total protein and creatinine concentrations did not show diurnal rhythms in either of the species.
  • 5.5. Blood values of the different parameters were studied on the basis of the ranges described in birds.
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