During a study on the parasitoids of the imported cabbageworm, Artogeia rapae (L.) (Lepidoptera: Pieridae), undertaken in 1993 and 1994, we recovered Cotesia rubecula (Marshall) (Hymenoptera: Braconidae) for the first time in Quebec, Canada. Samples were taken from pesticide-free plots of cabbage, broccoli, and Brussels sprouts located at Ste-Clotilde (45°09′N, 73°41′W) and L'Acadie, Quebec (45°18′N, 73°21′W), as described by Godin and Boivin (1998). In addition, survival of diapausing C. rubecula was evaluated after a 5-month incubation at 4°C (Godin 1997). Both A. rapae and C. rubecula are introduced species and originate most likely from Europe (Richards 1940). Artogeia rapae was discovered in 1860 in Quebec (Harcourt 1963), and C. rubecula was first reported in 1963 in British Columbia (Wilkinson 1966).

The spring emergence and seasonal abundance of the trivoltine spotted tentiform leafminer, Phyllonorycter blancardella (Fabr.), were monitored in a Connecticut apple orchard to provide phenological data for control programs. Spring emergence of each sex lasted 28 or 29 days in 1980 and 1981 although large emergences (≥5% of the total) occurred over a period of 12 to 18 days. When spring emergence was forecast in 1981 by using degree-day accumulations (above 5 °C) from the 1980 emergence, the predicted and actual 10 and 50% emergence time differed by 4 or 5 days. Even though daily catches of moths in pheromone traps preceded those in emergence traps, the abundance patterns indicated by these traps were similar. Low temperature and rain reduced emergence and flight activity. Seasonal abundance in pheromone traps showed three or four peaks, which usually decreased in size as the year progressed. From 1978 to 1981, the onset of male flight activity varied by as much as 3 wk. When emergence and pheromone traps are used together, they indicate the duration and peaks of emergence and flight activity.

Twenty-four species of parasitoids were found associated with the large aspen tortrix in interior Alaska. Keys are supplied for determining adults and, in the absence of adults, the parasitoids based on host stage and on late-instar larval remains. Brief biological and descriptive notes are given for each species appearing in the key.

The predominant predator of the pear psylla, Psylla pyricola Foerster, in a pear orchard on the Niagara Peninsula, Ontario was the anthocorid, Anthocoris nemoralis (F.). Applications of permethrin (62.5 g a.i./ha) reduced numbers of the predator when applied at petal fall. Azinphosmethyl (336.4 g a.i./ha) applied at petal and at 1st cover did not affect A. nemoralis. Both insecticides reduced the numbers of the predatory mite, Balaustium putmani Smiley. Species of Hemiptera other than A. nemoralis, especially Miridae and Reduviidae, were reduced by permethrin applied at petal fall and by azinphosmethyl applied at 1st cover.

Tarsonemus waitei Banks, 1912, T. setifer Ewing, 1939, and T. pauperoseatus Suski, 1967, are shown to be conspecific (new synonymy). Tarsonemus bakeri Ewing, 1939, thought to be conspecific with T. setifer for the last 25 years, is shown to be specifically distinct. Both sexes of these species are redescribed and reillustrated, and character state variability expressed within populations of T. waitei is discussed. The waitei species group, previously called the pauperoseatus group, is redescribed for these and other species. A provisional key to the known member species of this group is given. This group is judged to be insufficiently distinct from some of the other species of Tarsonemus to warrant recognition as a subgenus.

Bacillus thuringiensis (B.t.) + sublethal doses of the organophosphates fenitrothion or Orthene® were aerially applied to spruce budworm infested white spruce and balsam fir trees. B.t. + fenitrothion applied at 10 BIU + 17.5 g active ingredient in 4.71./ha (4 BIU + 0.25 oz in 0.5 gal/acre) and depositing at 1.5 to 3.0 BIU + 2.1 to 4.9 g/ha (0.03 to 0.07 oz/acre) did not protect the trees in the year of application owing to too low application rates but apparently gave good protection 1 year later without further treatment. A B.t. + Orthene combination applied at 20 BIU + 42 g/ha (8 BIU + 0.6 oz/acre) and depositing at the rate of 6.9 BIU + 12.6 g/ha (2.29 BIU + 0.18 oz/acre) provided good protection for both tree species in the year of spray.

Moth emergence was substantially reduced by 20 to 30 BIU B.t. + Orthene combination treatment. Thuricide fenitrothion, Dipel fenitrothion, and 30 BIU Orthene treatments reduced oviposition rate by at least 62%, 47%, and 47%, respectively. B,t. + a low dose of Orthene apparently had no major destructive effects on larval, pupal, or egg parasites whereas B.t. + a low dose of fenitrothion seriously reduced egg parasitism.

The data indicate the possibility of using B.t. in combination with low doses of chemical insecticides against the spruce budworm as an alternative to high doses of chemical insecticides alone.

The fecundity of the pea aphid Acyrthosiphon pisum (Harris) at 15 °C gradually diminishes as we diminish the daily photoperiod, this being maximum at 16 hours of photoperiod (55 ± 10 on variety Lincoln and 74 ± 15 individuals per parent on pea variety Perfection).

At 15 °C sex determination seems to take place between 12 and 14 hours of photoperiod, the critical phase for the change of sex being 13 hours 17 minutes of photoperiod for A. pisum. Maximum male production (57 – 63%) takes place at a photoperiod between 13 hours 4 minutes and 13 hours 36 minutes. A maximum of 90.5% of oviparous females was produced at a photoperiod of 12 hours and 10 minutes.

Efficiencies of light and pheromone traps were estimated from captures of moths emerging from pupae in the center of circular arrays of traps up to 200 m in radius. Light traps captured 1 insect for every 3.6 that passed through a linear meter at the trap, an efficiency factor of 0.28. This factor was constant for different insect densities. The pheromone traps were 3.5 times as efficient as light traps based on the captures of males only. The low efficiencies imply that the traps have a small zone of influence and several may be needed in a limited area to produce catches within reasonable confidence limits when populations are sparse and detection of increasing numbers has the greatest value.

Sexual dimorphism in size and shape has been studied in a wide range of organisms, but intraspecific variation in sexual dimorphism remains largely unexplored. In many parasitoid species the diversity of morphological-variation patterns within species is complicated by host effects. It is not known whether the magnitude and direction of sexual size dimorphism can be affected by the developmental environment (i.e., different host species). In this study we explored patterns of sexual dimorphism in size and shape in the aphid parasitoid Ephedrus persicae Froggatt. The analyzed sample consisted of 83 females and 54 males reared from five species of host aphids (Hemiptera: Aphididae) from various areas of the Palaearctic region. The most notable result of the study is that E. persicae displays divergent patterns of sexual dimorphism in body size and wing size: females have larger bodies than males, but males have larger wings. Our analysis of wing size and wing shape also showed significant within species variation in the degree and pattern of sexual dimorphism. Variation in wing shape between the sexes seems to be more conserved than variation in wing size. Variation in wing shape is influenced predominantly by host (biotype) and to a lesser extent by sexual dimorphism within a biotype.

Riegert et al. (1954) showed that nymphs and adults of Carnula pellucida (Scudd.) and Melanoplus mexicanus (Sauss.) released on bare, cultivated fields, dispersed up to 240 yards during six days. They showed no ability to orient themselves and move toward a food supply. Sixty per cent of M. mexicanus were within 50 yards of the release point after seven days. Experiments conducted from the Belleville laboratory in 1952 and 1953 showed that M. mexicanus dispersed less widely than this when released in a field population of grasshoppers, mostly M. mexicanus, where there was adequate food. This investigation was of special interest to the junior author (R. W. Smith), who was interested in relating the field distribution of adult parasites (as shown by the occurrence of immature parasites in captured grasshoppers) to various environmental factors. The validity of using such data for this purpose would depend upon the movement of the host from the time of parasitization to the time of capture. The following are details of the investigation.

Electrophysiological recordings are taken from the antennae of eastern spruce budworm males. These respond to crude pheromone extracts from the females. The pheromone receptors are located along the length of the antennae.

This paper describes females and some of the larval stages and male “puparia” for species of Lecanium known to occur in Canada. Also, it tenders a solution toward establishing a name for a North American species that has been confused with L. corni Bouché as identified by Marchal (1908).

The Northwestern Queen Elizabeth Islands, i.e., Meighen, Ellef Ringnes, Amund Ringnes, King Christian, Lougheed, Borden, Mackenzie King, and Brock, constitute the most barren part of the high arctic fell field. Within this group, the richest area is at Isachsen on Ellef Ringnes Island; there the relief is higher and the variety of habitats greater and richer than at any other place on any of these islands. Despite this relative richness, however, Isachsen has the coldest summer climate of any arctic weather station (July mean, about 38°F.) and the smallest arthropod fauna (55 species of spiders, mites, collemboles and insects, according to studies conducted there in 1960) of any locality investigated during the Northern Insect Survey.

Pissodes yunnanensis Langor et Zhang, a pest of Yunnan pine, Pinus yunnanensis Franchet, in southwestern China, occurs at elevations of 2200–2800 m. These weevils infest Yunnan pine trees less than 20 years old but prefer trees 8–10 years old. Oviposition occurs mainly along the upper trunk on current-year and 1-year-old growth and occasionally on the upper lateral branches. Weevil feeding often kills the leader, which results in stem forking and crooking. At times, after 2–3 years of consecutive severe infestation, tree mortality occurs. In southwestern Yunnan Province, adults of this univoltine weevil emerge from infested stems from mid-April to mid-July. Eggs appear in late June, first-instar larvae in early July, and fourth-instar larvae in late March of the next year. First- and second-instar larvae feed in the phloem, and third-instar larvae move to the sapwood or pith, where they overwinter. In March, larvae resume feeding and development. Fourth-instar larvae excavate pupal chambers (chip cocoons) in the outer sapwood or pith, and pupation occurs from late March to late May. Optimal development of eggs and pupae occurs at 25 °C in the laboratory. Parasitism is the main cause of mortality in P. yunnanensis, accounting for 2%–25% of mortality among third- and fourth-instar larvae and 5%–10% among pupae.

Bombus iridis phaceliœ, n. var.—♀. Hair of face black, with a little pale intermixed; yellow hair of thorax in front dense, not at all mixed with black; yellow of scutellum neither divided nor mixed with black; hair on inner side of basal joints of tarsi dark; hair on second and third abdominal segments entirely deep red (much less dense, and not nearly so bright as in B. ternarius), but second with a large bare median triangle; hair of fourth segment and sides of fifth yellow.

The larvae of the following species of Dytiscidae are described and figured: Laccophilus maculosus (Germ.), L. biguttatus Kirby, Liodessus affinis (Say), Hydroporus notabilis Lec, Hygrotus punctilineatus (Fall), Hyg. tumidiventris (Fall), Hyg. punctatus (Say), Hyg. patruelis (Lec.), Hyg. impressopunctatus (Schall), Hyg. canadensis (Fall), Hyg. sellatus (Lec.), Laccornis conoideus (Lec.), Rhantus notatus Fab., Colymbetes sculptilis Harr., Agabus clavatus Lec., A. discolor Harris, A. bifarius (Kirby), A. ontarionis Fall, Graphoderus zonatus (Hoppe), Acilus semisulcatus Aubé, Hydaticus stagnalis (Fab.), Dytiscus sublimbatus Lec., D. dauricus Gebler, and D. fasciventris Say. All were collected at Delta, Man.

In Gatineau Park near Ottawa Simulium venustum adults were present in appreciable numbers around man (usually 20-100 flies/man/hr.) only between mid-May and mid-June in 1958-60, numbers after late June being negligible apparently because a succeeding generation failed to mature in significant quantity. It is suggested that differences in the duration of the S. venustum biting problem in different parts of eastern Canada largely depend on whether or not streams remain suitable for the aquatic stages after the spring generation derived from overwintered eggs has emerged.

In sweep-net catches of flies attracted to man at fixed sites the proportion of parous flies was nil in mid-May and increased to near 100 per cent by mid-June, 3 change sometimes interrupted by the appearance of a second wave of nulliparous individuals from late fly-producing streams. The latter were anatomically indistinguishable from flies produced earlier apart from reduced body size. The results suggest that the populations studied were anautogenous and that there was no deviation from this condition that could be attributed to variations in the food available for larvae in different streams or at different times.

The proportion of attracted parous flies containing relict eggs sometimes tended to increase towards the end of the season, suggesting that a large proportion of the few flies still remaining had completed two or more ovarian cycles.

Parous flies tended to be particularly active in late afternoon and evening but instances when this diurnal pattern did not occur were observed.

The rate of ingestion by Podisus maculiventris Say feeding on larvae of Tenebrio molitor L. or Galleria mellonella L. is almost constant with time and from one predator to another. The rate is 1.80 ±.070 mg/hr/individual.No effect of the age or size of the predator nor of the species of prey on the feeding rate could be detected. Different periods of starvation before feeding directly affect the percentage of individuals that feed, but not the actual rate of feeding, until 60 hours of starvation. After 72 hours starvation, there is a drop in the feeding rate which we attribute, tentatively, to a weakening of the feeding mechanism by the starvation.The initial weight of the larva used as prey affects the rate of sucking during the first hour or two of each period of feeding and this relationship is responsible for a slight non-linearity in the individual curves of feeding. This may be an effect of the internal pressure of the body fluids in the prey.The process of ingestion is reviewed and compared with published studies of other species of Hemiptera. It is suggested that after insertion of the stylets of the predator into the body of the prey, the feeding process is affected by the internal pressure of the prey during the early part of a period of feeding but that, thereafter, the sucking action is maintained constant by the action of capillarity and the pharyngeal pump.

The life history and ultrastructure of the protozoan Malameba locustae (King and Taylor) were studied in the migratory grasshopper Melanoplus sanguinipes (F.) using feeding and injection studies. Insects fed cysts developed infection in the Malpighian tubules 5–6 days later; no trophozoites were observed in haemolymph samples taken 2–20 days post-feeding. After excystment, a few trophozoites entered the midgut epithelium and many were located near the basement membrane of the epithelial cells, where they appeared to degenerate. Trophozoites were not seen to divide in the midgut epithelium, and apparently did not damage this tissue. Trophozoites injected directly into the haemocoel could not be recovered even 4 h after injection, and the Malpighian tubules did not become infected. It was concluded that trophozoites did not penetrate the midgut to enter the haemocoel or move through the haemocoel to infect the Malpighian tubules, but instead probably entered the tubules directly from the gut. Trophozoite ultrastructure in midgut and Malpighian tubules, and cyst wall deposition were described.

Factors affecting the extraction and bioassay of the sex pheromone of white-marked tussock moths were evaluated. Dipping the female pheromone glands in a solvent (preferably hexane) to produce a wash containing active material was a particularly effective and reproducible method of obtaining a potent extract. These were most active if obtained from virgin females < 2 days old. Extracts from recently mated females were only slightly less active than those from virgin females. Males were most responsive in bioassays when 2 to 3 days old. The maximum percentage response of males was obtained at 1 × 10−4 FE (female equivalents); beyond this concentration the percentage response decreased. Characteristically, extracts lost their potency within 1–3 weeks of preparation. It is suggested that either an inhibitor or loss of a chemical component of the sex pheromone causes an extract to become inactive.