The abdomen of female Pelecinus is uniquely and extremely modified for digging in soil. Segments 2–7 are connected by sternite to sternite articulations allowing vertical movement produced by anteriorly placed muscles acting through long tendons inserting on the adjacent succeeding segment. Segments 3–6 have, in addition to the linkage allowing vertical movement, a detached, posterior section of the sternite that can rotate on a median ventral flexible attachment to the tergal margins. This linkage allows the posterior section of a sternite together with the succeeding segments to rotate through about 135 °relative to its tergite. Tergite 8 bears large spiracles completely covered by sternite 7. The ovipositor lacks the usual 3rd linkage between gonocoxite 9 and gonapophysis 9, allowing the depressor muscle of the gonapophysis to extrude the ovipositor directly backwards.

Two subspecies, Troides amphrysus chrysomelas new subspecies and T. helena bunguranensis Ohya, from Natuna islands, Indonesia are described.

A new species, Chironomus (Camptochironomus) vockerothi, is described in the adult male and female from Alberta and is compared with other species in the subgenus.

Trichogramma minutum Riley was released in the field for suppression of epidemic spruce budworm, Choristoneura fumiferana (Clemens), egg populations in Maine from 1977 to 1981. Commercially reared California-strain T. minutum were released from the ground at single-point sources in 1977. In 1978, using 4-point-source releases, we found that the native Maine-strain performed better than the California strain. In 1979, broadcast and multiple releases from the ground gave slight improvement in parasitism over 4-point releases. In 1981, three closely timed, aerially broadcast releases from a helicopter yielded increases in parasitism rates significantly higher than those in control plots, but not sufficient to suppress epidemic spruce budworm populations. Important variables and suggestions for future aerial releases are discussed.

A revised generic description of the three larval instars of Omophron is presented. Hypothetical apotypic character states of the genus are: bidentate retinaculum; lacinia subequal in length to galea and apically subspatulate; ligula as long as labial palp; pore LAa located on ligula and seta LA6 on basal third of ligula; setae TI2* and TI7* of middle and hind tibiae located basally; setae UN1 and UN2 flat and about 1.5 times the length of claws; presence of serially paired gland-like structures on abdominal pleura I–VII; hypopleurites not apparent in first instar; apex of urogomphi extended as a small hyaline appendix in first instar; setae PY1, PY2, and PY6 on the pygidium absent. Most of these character states are autapotypic, and no synapotypies were found to indicate a sister group to Omophron.

Adult flies of the apple maggot, Rhagoletis pomonella (Walsh), were monitored for 6 years at Guelph, Ontario using aerial and ground-emergence traps. Two degree-day (°D) models to predict adult emergence were tested. Fifty percent of the adults were captured in an average of 809 ± 50 (SD) °D8.7 and first capture was at 638 ± 60°D6.4. Degree-day models which have been proposed previously and those developed in this study were only slightly more accurate than average calendar date for predicting adult emergence. Differences in °D requirements for emergence in each year were correlated with the length of cold period and the correlation suggested that the length of cold period preceding morphogenesis affects either the number of °D required to complete postdiapause development or the threshold temperature for development.

The presence of the fungus Phoma macdonaldii Boerema on the exocuticle of the adult stem weevil Apion occidentale Fall, was verified using isolation techniques and scanning electron microscopy. Pycnidiospores matching those of P. macdonaldii in size and shape were observed on the antennae, meso- and metathoracic legs of both field-collected and Phoma-incubated adults. Fungal hyphae were observed on the rostrum of both field-collected and laboratory-inoculated adults. Four percent of the weevils carried P. macdonaldii internally.

An analytical method for the description of intrinsic variability in insect development rates for incorporation in phenology models is presented. Two sets of experimental data are used as examples. The method is easy to apply, can describe data accurately, produces highly realistic simulations of insect development, and is amenable to the simulation of age-dependent mortality, feeding, and reproduction. The method was developed for univoltine insects with discrete generations, but it can also be applied to multivoltine species with overlapping generations. A modification of the method to handle small samples is also discussed and applied to data.

The genus Sinierus Distant contains three distinct species. The genus and the type-species S. capensis (Dallas) are redescribed, the latter being reported widely from Africa. Two other species are described as new, S. explanatus from tropical Africa and S. nudus from Madagascar. A key to species is also presented.

Two new species of Aphis L. are described, holodisci from British Columbia and Oregon, and schuhi from Oregon, both from Holodiscus discolor Maxim.

The imported crucifer weevil, Baris lepidii Germar, was sampled in commercial horseradish fields by pitfall traps, visual counts, baits, soil cores, and square area removal. Adult counts from soil cores taken directly over the plant crown were closely related to those from 0.25 m2 samples centered around the whole plant. Numbers of adults determined by relative sampling techniques such as visual counts, pitfall traps, and baits were not closely related to the number of adults recovered in soil cores. All of the fields examined had adult weevils present at planting time as indicated by bait catches. No sampling method was an adequate predictor of the percentage of horseradish roots infested with B. lepidii at harvest.

Tumblers used to remove debris-feeding insects, predators of the leafcutter bee, excess leaf pieces, debris, and plant foliar molds from cells of the alfalfa leafcutter bee were compared. A hand-cranked tumbler removed significantly more material than did five motor-driven tumblers. It also removed more debris as the initial sample weight increased.

Thuricide and Dipel, formulations of Bacillus thuringiensis (B.t.), were applied aerially against the spruce budworm, Choristoneura fumiferana (Clem.), in forest stands of balsam fir, Abies balsamea L. A dosage of 30 Billion International Units (BIU) of B.t./ha applied in 2.4 to 4.7 L of spray/ha was most effective. Application of 20 BIU/ha was marginally effective against a population of 12 to 36 larvae/45 cm of branch.

The true armyworm, Pseudaletia unipuncta (Haw.), has no evident diapausing stage, is not freeze tolerant, shows no consistent seasonal changes in either supercooling-point values or longevity at 0 °C for different developmental stages, and did not survive when held in overwintering cages in the field. These facts support the hypothesis that this species cannot overwinter in Quebec and that the adult populations observed each spring must therefore be the result of a northerly migration from sites, such as Tennessee, where overwintering is known to occur.

The number of moths captured during short intervals in traps containing a sex attractant for males of the bertha armyworm, Mamestra configurata Wlk., is related to the stage of plant development in the fields of canola (oilseed rape, Brassica napus L.) in which the traps are placed. More moths were captured in fields with plants in the early bloom stage than in those with plants in earlier (leaf, bud) or later (late bloom, pod) stages of development. The effect of this relationship on the total number of moths captured in any field during the entire period of moth flight depended in part on the synchronization of crop development with moth flight. Neither the total number of moths captured per field nor larval density were significantly related to crop development because of high inter-field variability among groups of fields with similar patterns of crop development. Early-maturing fields contained older larvae than later-maturing fields so they should be sampled first to determine larval density and the need for insecticidal application. The estimated patterns of egg-laying were similar to those for male moth capture in early-, mid-, and late-flowering fields. Therefore, male moth captures in sex attractant traps provide a valid index to the abundance of female moths and their egg-laying activities.

The chemicals cis (Z) and trans (E)11-tetradecenyl acetate (11–14:Ac), trans 11-tetradecen-1-ol (E11–14:OH) and trans 11-tetradecenal (E11–14:Ald) were isolated from unmated female Choristoneura orae Freeman and shown to be highly attractive when used as lures in sticky traps. The identification of these components of the sex pheromone facilitates the separation of C. orae from other Pinaceae-feeding Choristoneura in the same area.

The seasonal distributions of Choristoneura occidentalis Freeman and C. retiniana (Walsingham) males attracted to pheromone sources overlapped considerably at two sites in south-central Oregon. Bimodality in the seasonal distributions of trapped males of both species was associated with a period of cool weather. The daily periods of female calling, and attraction of males to female-baited traps and to chemically baited traps overlapped greatly between the two species. However, these three aspects of C. occidentalis mating behavior began 1–2 h before those of C. retiniana. Under laboratory conditions, there was also considerable overlap in the calling periods of the two species; but again, C. occidentalis females initiated calling slightly earlier than did female C. retiniana. Females of both species continued to call many hours past the cessation of male attraction to pheromones in the field. Male attraction to pheromones occurred earlier on cool evenings than on warm evenings. Laboratory studies indicated a similar effect of temperature on timing of female calling. Little intraspecific variation in calling periodicity was observed among field-collected populations of each species. However, a C. occidentalis laboratory colony appeared to have partially lost its circadian rhythm of calling.

Yield saved by insecticidal applications against the bertha armyworm, Mamestra configurata Walker, in commercial fields was measured by comparing yield in protected (unsprayed) plots of 74.4 m2 and in adjacent sprayed areas. Coefficients of variation of yield from sample units 2, 1, and 0.5 m2 ranged from 0.12 to 0.51; statistical precision was increased by taking twenty-five 0.5 m2 sample units per plot. Analysis of pod damage from selected plants predicted percentage yield loss equal to that determined by area sampling.

The results showed that yield saved by control in commercial situations did not exceed 0.325 g/larva, a value that was determined in previous work by field cage trials. Using 1981 costs for spraying and rapeseed prices and a yield loss of 0.325 g/larva, the break-even point for cost-benefit occurs when larval density is 23/m2, a value double the currently recommended density of 10 to 12/m2. Many rapeseed growers therefore are controlling the bertha armyworm at net economic loss, a situation verified by an analysis of 42 separate control decisions made by growers in 1981.

To our knowledge, reports of Betula spp. resistance against damage caused by the birch leafminer, Fenusa pusilla (Lepeletier), have not been published. Becker (1938), Friend (1933), and Johnson and Lyon (1976) stated that B. populifolia Marsh., B. papyrifera Marsh., and B. alba L. are the most commonly attacked species. Friend (1933) and Johnson and Lyon (1976) stated that B. lenta L., B. alleghaniensis Britt, and B. nigra L. have never been observed infested or are rarely fed upon.

The type material, added to the Coleoptera Section of the Canadian National Collection of Insects from 1 January 1974 to 31 December 1980, is catalogued. This new material consists of 416 holotypes, 188 allotypes and 4 neotypes; 2 species are represented by syntypes and 718 by paratypes or paralectotypes. The reference to the original description for each species is cited. All data associated with the specimens are quoted, except in the case of paratypes, paralectotypes and syntypes.