Application of petroleum oils prior to oviposition by overwintering pear psylla, Psylla pyricola Foerster, reduced oviposition by 98% for up to 5 weeks. The delay of oviposition and reduction in subsequent egg and nymph densities were inversely proportional to the rate of oil used. The reduced oviposition rate was due primarily to inhibition of oviposition by oil deposits on the host, not adult mortality. No commercially important deleterious effects of oil treatments were detected on several pear varieties.

Seven species of Culicoides were collected from aerial sweeps about man or from aspiration of biting midges from man in Nova Scotia and New Brunswick. Hourly sweep netting indicated C. biguttatus was diurnal in this region and was apparently limited in its dispersion. Culicoides sanguisuga was the most widely distributed species of those collected in the region. A checklist of the 15 species of Culicoides now known from New Brunswick and Nova Scotia is included.

Total foliage consumption per larva of Heterocampa manteo (Doubleday) was 334 ± 49.3 cm2 of leaf area. Approximately 85% of the consumption occurred during the fifth larval stadium. There was no significant difference in consumption by H. manteo when fed northern red oak, Quercus rubra L., or white oak, Quercus alba L. Foliage consumption at 27 °C, 24 °C, and 21 °C did not differ significantly; but larvae reared at 15.5 °C consumed 42.6% less foliage. Larvae parasitized by Diradops bethunei (Cresson) consumed 61.3% less foliage than non-parasitized larvae reared at the same temperature. Two methods of predicting defoliation are discussed based upon larval foliage consumption data.

Analysis of samples taken during different stages of the cleaning process for certified timothy seed following harvest showed high densities of European skipper eggs in the waste. These eggs could represent a source of infestation of this insect as the waste is not destroyed but used as lawn seed or discarded on the farm.

Southern pine beetles (Dendroctonus frontalis) carrying phoretic Trichouropoda australis deutonymphs were caught in bucket traps baited with frontalin-alpha pinene at heights of 3, 6, and 9 m on the boles of loblolly pines. Of 8475 beetles collected, 36.3% carried uropodids or their pedicels. Beetles trapped at 3 m carried more pedicels than those trapped at 6 or 9 m, indicating that the flight of beetles is influenced by the presence of phoretic mites. Re-emerging parent beetles can be differentiated from brood adults by the color of the mite pedicels.

Entomophthora culicis (Braun) Fresenius was found parasitizing adults of Simulium venustum Say and Simulium vittatum Zett. in central Alberta. The first parasitized black fly adults were collected on 17 August 1973 from a moist log on the margin of Flat Creek (113°52′ W. long., 54°41′ N. lat.). In subsequent summers, parasitized black flies were found on various substrates at sites on three other creeks in the area. Parasitized black flies first appeared in late June and were present to mid-September with peak numbers occurring during August. The fungus kills young black fly adults. This is the first record of E. culicis on black flies in Canada.

Survival and development rates were obtained for the cereal leaf beetle, Oulema melanopus (L.), at 12 constant temperatures. Rates of survival for eggs were high at temperatures ranging from 12°C to 32°C, but none hatched at 6°C or 34°C. Larvae survived at 8° to 32°C with no drastic rise in mortality at the extremes; mortality at 34°C increased with larval age. Pupal survival was low at all temperatures from 8°C to 32°C, ranging from about 3% at these limits to 40% at intermediate temperatures (14° to 30°C). Duration of egg and larval stages decreased with rise in temperature up to 30°C, and that for pupae, up to 32°C. Developmental rates plotted against temperature did not deviate significantly from fitted curves of the form 1/y = K/(1 + ea-bx).

The threshold for complete development was at some point between 6°C and 8°C. Thermal requirements, with 7°C as developmental zero, were calculated at 105, 41, 36, 43, 46, and 282°D, respectively, for the eggs, the four larval instars and the pupae. Accumulated heat units (°D7) during development of O. melanopus in field plots at Ottawa did not differ significantly from those expected. Similar calculations using a base of 9°C (ca. 48°F) predicted development equally well.

Direct observation (DO) of arthropods on soybean plants was compared with another absolute method, clam trap (CT), and with sweepnet (SW) sampling during a season-long investigation of the colonization by arthropods of two east central Illinois soybean fields. In terms of number of species detected, DO vs. CT showed good agreement between the two fields, while DO vs. SW showed poor between-field agreement. Proportion of similarity (PS) and quotient of similarity (QS) values were higher in a DO-CT comparison than in a DO-SW comparison. Performance similar to that of the other absolute method, consistency of results, ability to use the method throughout the entire season, relatively high numbers of species and individuals detected per unit area sampled, relatively short time required to sample a site, and the capability of yielding a precise record of important interactions among soybean arthropods indicate that direct observation is an effective method for sampling the arthropod community on a row crop such as soybean.

Collections of Amitus (Hymenoptera: Proctotrupoidea, Platygastridae) from the Western Hemisphere are referred to the following species: from Canada and the United States, A. aleurodinis Haldeman, A. granulosus n. sp., and A. gibbosus n. sp.; from Mexico and South America, A. spiniferus (Brethes), A. pigeanus n. sp., A. hesperidum Silvestri, and A. fuscipennis n. sp.

A lateral plate-like process on the male fourth antennal segment is regarded as a phenocline, characteristic of species or species groups.

The spectrum of contact toxicity and activity in soil of four pyrethroid insecticides was assessed in the laboratory. Pyrethroids tested were: FMC 33297 (3-phenoxybenzyl (±)-3-(2, 2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate); Shell WL 41706 (alpha-cyano-3 phenoxybenzyl 2,2,3,3-tetramethylcyclopropanecarboxylate); Shell WL 43467 (alpha-cyano-3-phenoxybenzyl 2-(2,2-dichlorovinyl)-3,3-dimethylcyclopropane-1-carboxylate); and Shell WL 43775 (alpha-cyano-3-phenoxybenzyl-2-(4-chlorophenyl)-3-methyl-1-butyrate). Chlorpyrifos and carbofuran, two broad spectrum contact and soil insecticides were included for comparative purposes. Spectrum of contact toxicity was determined using 24–48 h nymphs of the common field cricket, Acheta pennsylvanicus (Burmeister), 24–48 h onion maggot adults, Hylemya antiqua (Meigen), 3rd instar dark sided cutworms, Euxoa messoria (Harris), northern corn rootworm adults, Diabrotica longicornis (Say), and honeybees, Apis mellifera L. Crickets were used to assess insecticidal activity in soil relative to soil moisture, type, and temperature. The pyrethroids were effective contact insecticides comparable in toxicity and spectrum of activity to chlorpyrifos and carbofuran. They were particularly toxic to the darksided cutworm. They were less effective in mineral soil than chlorpyrifos. WL 43467 showed activity in mineral soil close to that of carbofuran, while the other pyrethroids were less active. Activity in soil was influenced by soil moisture and type. In contrast to the standard insecticides the pyrethroids generally showed a negative temperature coefficient of toxicity in soil.

Newly hatched larvae of Chironomus decorus, Endochironomus nigricans, and Chironomus staegeri mostly from a single shallow eutrophic pond near St. Catharines, Ont., were reared to the adult stage at 15°C and 20°C and 16 and 8 h daily photoperiods. Normal development to EM50 took 26 days at 20°C and 37 days at 15°C in C. decorus; 35 and 48 days in E. nigricans; and 68 days at 20°C in C. staegeri. The 8 h daily photoperiod inhibited emergence, by preventing pupation of final instar larvae, in E. nigricans and C. staegeri at both temperatures, and in C. decorus at 15°C. Nevertheless, a few individuals emerged even under these conditions; such individuals may be important in insuring field populations against environmental variation.

Food supply was normally adjusted to permit only partial emergence even in non-inhibiting regimes. After initial emergence was complete, more food was added to some replicates. In suitable regimes, remaining larvae then completed metamorphosis. Larvae undergoing delayed metamorphosis (for whatever reason) suffered mortality at low food levels; this suggests that food was required for maintenance even by individuals in which metamorphosis was inhibited by photoperiod/temperature combinations alone.

After a further period, when any food-induced emergence had been completed, transfers to higher temperatures or longer photoperiods were made. Transfer after initial inhibition to regimes that normally permitted emergence resulted in emergence; and in E. nigricans transfer at 8 h photoperiod from 15 °C to 20 °C also resulted in emergence, suggesting that the cues for induction and termination of dormancy are not the same, since 8 h photoperiod normally induces dormancy at both temperatures. Emergence after such transfers was more highly synchronized than in the initial period, but protandry was generally retained.

The niche breadth and overlap in nesting preferences of 15 species of bumble bees were investigated in Alberta. Some of the factors that influence the distribution of nesting sites and abundance of species and permit the species to coexist in sympatry are discussed. Artificial domiciles were used as potential nesting sites. Some species were specialists in terms of nest site selection while others were generalists. The few natural nests found, the long periods spent by queens searching for nests, the high frequency of usurpation or direct interference and death of intruders, and the frequency of high niche overlap values between species are evidence that nesting sites are limited and are incompletely partitioned among the coexisting species. Usurpation also demonstrates the competition among individuals and species. Phenological differences in nest establishment influence the competition among the species. Camouflaging of tunnels presumably reduces the intensity of usurpation and protects queens and the brood from inclement weather and from social parasites (e.g., Psithyrus) and predators.

In field trials conducted at Guelph, Ont., methoprene (Altosid® SR-10) at 0.028 kg AI/ha (0.025 lb AI/ac) effectively controlled spring Aedes species following treatment of third- and fourth-instar larvae. However, when treated in the first to third instar, only partial control was obtained. The formulation remained active in the pools for 13 days during which time the average temperature was < 20°C. Methoprene also effectively controlled early-summer Aedes vexans (Meigen) after treatment of fourth-instar larvae. Diflubenzuron (Dimilin® 25% WP) at 0.022 kg AI/ha and 0.045 kg AI/ha (0.02 and 0.04 lb AI/ac) was effective against spring Aedes species following treatment of third-instar larvae.

Selected insecticides were topically applied to different populations of the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough). For each insecticide, the hypothesis of equal response curves was rejected by the likelihood ratio test. Even for two successive generations of the same populations, the hypothesis of equality was not accepted for some insecticides. Chemical control programs directed at different populations of this insect may be adversely affected by such variations.

While there is much evidence for interrelationships between the organic components of insect diets as they relate to growth, there is very little information available on inorganic or organic-inorganic relationships. An example of inorganic interactions is found with Cu and Zn in the house cricket, Acheta domesticus (L.) (McFarlane 1976a).Organic-inorganic interactions have been shown by Fraenkel (1958), who demonstrated effects of Zn and potassium on the expression of a carnitine deficiency in Tenebrio molitor, and by McFarlane (1974), who showed an interaction between Cu and vitamin E in the house cricket.

This note reports the first in vitro oviposition and rearing of a parasitic insect, the endoparasitoid wasp Itoplectis conquisitor (Say), a male, on an artificial host consisting of an encapsulated synthetic, or meridic (Dougherty 1959, p. 53), medium.

Parasitic insects, of course, have been reared in vitro on meridic diets (House 1954; Yazgan 1972; Thompson 1975). Some were reported to oviposit into artificial objects (Arthur et al. 1972; Rajendram and Hagen 1974; Hoffman et al. 1975). Trichogramma pretiosum Riley laid viable eggs and development to adults occurred in small wax-resin spheres filled with host haemolymph (Hoffman et al. 1975).

Clastoptera arborina Ball is placed as a senior synonym of C. newporta Doering. C. doeringae n. sp. is described for the species previously reported as “arborina” by Doering (1928).