The natural occurrence of beauveriosis in Dryocoetes confusus (Swaine) in Abies lasiocarpa (Hook.) Nutt. in British Columbia is reported, and the pathogenicity of Beauveria bassiana (Bals.) Vuill. isolated from D. confusus was confirmed experimentally. Also, direct observations of newly established pairs of D. confusus in glass – phloem sandwich cultures showed that cadavers of B. bassiana-killed females were walled-off with frass by healthy males.

Trechus quadristriatus (Schrank), a Palaearctic species, is reported for the first time from North America. The species is briefly described and compared with T. obtusus Erichson. The key to Trechus of Canada by Lindroth (1961: 192–194) is modified to include T. quadristriatus.

Embryological development and hatching for the red turnip beetle, Entomoscelis americana Brown, were studied at 20 °C. In eggs kept at this temperature for > 12 days, embryological development proceeded until a late stage embryo was formed, at which time the embryo entered diapause for the winter. The time required for 50% of the eggs to reach the late embryo stage was estimated to be 11 days. The late embryo stage was not reached before winter in eggs kept at 20 °C for < 11 days, but most of them survived and hatched. Embryogenesis proceeded normally after winter without any apparent adverse effects, and hatching was delayed by the amount of time required to complete embryogenesis. Although it was not essential for the eggs to reach the late embryo stage to overwinter successfully and hatch, a critical minimum stage of development had to be reached during embryogenesis for the eggs to survive. The critical minimum stage of development occurred in the germ band formation stage and was reached during the first 1.5 days of embryogenesis. Most of the eggs laid from 1 to 15 September 1980 and kept outdoors reached the late embryo stage before winter and hatched the next spring; those laid from 15 September to 15 October reached the critical minimum stage of development before winter and also hatched successfully; and those laid after 15 October did not hatch, because they apparently had not reached the critical minimum stage. An evaluation of the data for the eggs kept outdoors and of atmospheric air temperature data suggested that embryo death due to eggs not reaching the critical minimum stage of development before winter normally should not be an important factor in the population dynamics of E. americana in the rapeseed- and canola-growing areas of western Canada. The ecological significance of the data is discussed.

On 19 August 1982, a female noctuid moth resembling the Palearctic species Noctua pronuba (Linnaeus), which has recently been introduced into Eastern Canada (Neil 1981), was collected at an ultraviolet light at Simon Fraser University, Burnaby, British Columbia. An additional specimen, a male, was taken 13 September 1982. A third was seen, but not captured, 2 September 1982. A comparison of the British Columbia material with figures and descriptions of other Noctua species given by Bretherton et al. (1979) revealed them to represent Noctua comes (Hübner), based on their smaller size, light brown, narrow primaries, and well defined discal dot on the secondaries. This preliminary identification was later confirmed by external morphological and genitalic comparison with specimens of various Noctua species obtained from the Nova Scotia Museum collection in Halifax.

Mean catches of Phyllotreta striolata (F.) in allyl isothiocyanate baited traps decreased southwards from the boreal forest and northern parkland to the central parkland of Saskatchewan, while the opposite was true for Phyllotreta cruciferae (Goeze). Similar trends in the relative numbers of the two species were evident in sweep net catches in canola crops.

The sex pheromone of bertha armyworm, Mamestra configurata (Walker), was reported to be (Z)-11-hexadecenyl acetate (Z11-16:Ac) and an unidentified tetradecenyl acetate. Electroantennogram responses of male antennae to synthetic isomeric tetradecenyl acetates and attractancy tests under field conditions showed that the highest number of males were captured with a blend of Z9-14:Ac: Z11-16:Ac in a ratio of 1:19 (Underhill et al. 1977). This blend has been useful for monitoring the relative abundances of bertha armyworm; however, in 162 monitor traps in southern Alberta from 1979 to 1982, the catches consisted of 18.4% Agroperina cogitata (Sm)

Both sexes are described for the species pair of crab spiders, Xysticus durus (Soerensen) and X. keyserlingi Bryant. A recent collection of keyserlingi from the Alpine Garden, Mt. Washington, New Hampshire reveals that the male of X. leechi Turnbull et al. has been misidentified as that of durus, the male of durus has been confused with that of keyserlingi, and the name leechi must become a junior synonym of the name keyserlingi.

Drift of aquatic arthropods was not uniformly distributed by depth in a stream and differed from one reach to another. Drift of terrestrial arthropods, although usually densest at or near the surface, was also substantial at depths. Nets for sampling of drift should extend to the bottom and include the surface.

A substantial amount of the mustard and a small amount of the canola seed produced in the prairie provinces in 1983 was downgraded due to excessive content of insect frass. Because the frass was similar in size to the seed, much of it was not removed by the usual cleaning processes. Most seriously affected was mustard seed which has a contamination limit of 1 frass pellet per 500 g for grade Nos. 1, 2 and 3 Canada and 0.005% by weight for No. 4 Canada (Can. Grain Comm. 1983). Initially the limit for canola was 0.02% by weight based on tolerances established for rodent (vertebrate) excreta. Because insect (non-vertebrate) excreta is less detrimental than rodent excreta, the limits for non-vertebrate excreta in canola marketed within Canada were increased to 0.1%, 0.2% and 0.3% for grades No. 1, 2 and 3 respectively (per. comm., L. Sequin, Deputy Director, Standards and Technology, Canadian Grain Commission). The previous limit of 0.02% remains in effect for canola entering the export market. Similar consideration was given to revising the limit for insect excreta in mustard seed but no change was made because the quality criteria are quite different; canola is extracted for its oil whereas mustard seed may undergo little processing before being consumed.

The pecan weevil, Curculio caryae (Horn), is a native American species that was first described by Horn (1873) from specimens bred from hickory nuts at Brooklyn, New York. It has been regarded as an obligatory feeder on nuts of the genus Carya (Gibson 1969; Harris 1983), and is especially troublesome in commercial hickory nut and pecan orchards.

Abundance and seasonal distribution of adult Tabanidae were studied in Poste-de-la-Baleine (55°17′ N; 77°45′ W) and in Richmond Gulf (56°09′ N; 76°39′ W), two areas of the forest-tundra located along the eastern shore of Hudson Bay. Fourteen species were collected at Poste-de-la-Baleine (7 Chrysops and 7 Hybomitra) and eight species in the Richmond Gulf area (3 Chrysops and 7 Hybomitra). Chrysops nigripes, H. aequetincta, H. arpadi, H. astuta, H. lurida, and H. frontalis are Holarctic species. The dominant species at Poste-de-la-Baleine were H. lurida (29.5%), C. furcatus (22%), C. excitans (18%), H. hearlei (11.9%), and H. frontalis (11%). Two species were dominant in the Richmond Gulf area: H. frontalis (83.9%) and C. sordidus (12.2%). Hybomitra lurida was the earliest species, collected a few weeks before others. Results were compared with the few previous North American studies made in such northern localities.

A key to females is presented for six euphorine species that parasitize adults of crucifer-infesting flea beetles. Five of the species, Townesilitus psylliodis (Loan), Microctonus punctulatae sp. n., M. pusillae Muesebeck, M. vittatae Muesebeck, and M. zimmermanni sp. n., are Nearctic in distribution; the sixth, T. bicolor (Wesm.), was recently introduced into Manitoba from Europe. The two new species are described, and biological information is presented for T. bicolor, T. psylliodis, M. punctulatae, and M. vittatae.

The spotted tentiform leafminer, Phyllonorycter blancardella (Fabr.), is an important pest of apple in Ontario (Pree et al. 1980), Michigan (Dutcher and Howitt 1978), and New York (Weires et al. 1980). In Ontario, the leafminer has three generations per year (Johnson et al. 1976) and overwinters as a diapausing pupa in the leaf litter (Trimble 1983). Considerable variation exists in the reported fecundity of P. blancardella. For example, Bagdavaze (1963) found that females laid from 11 to 33 eggs whereas Baumgartner et al. (1981) reported an average of 102 eggs per female. One possible source of this variation could be the availability of carbohydrate to ovipositing females as was suggested by the results of Pottinger and LeRoux (1971) who studied a Quebec population of P. blancardella. The objectives of the present study were to determine the effects of carbohydrate on female longevity and fecundity (number of eggs laid) and egg viability.

Flight of the range caterpillar occurred predominantly at dusk in the grasslands of eastern New Mexico in 1979 and 1980. The restricted period of flight in the evening corresponded to cool temperatures which probably favored mating success. Changes in atmospheric temperature and pressure had little effect on the number of moths flying from day to day. Most females oviposited within 10 m of the site of pupal eclosion.

Cone and seed insects frequently cause severe losses to Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seed production in the Pacific Northwest (Hedlin et al. 1981; Ruth 1980). Two of the major species west of the Cascades are the Douglas-fir cone gall midge (Contarinia oregonensis Foote (Diptera: Cecidomyiidae)) and the Douglas-fir seed chalcid (Megastigmus spermotrophus Wachtl. (Hymenoptera: Torymidae)). These two species are host specific on Douglas fir and exhibit an extended diapause in which more than 50% of each year's cohort may remain in diapause under host trees for 1 or more years (Annila 1982; Hedlin 1961; Hedlin et al. 1981; Johnson 1962). The economic and biological costs of chemical control have supported recommendation of alternative control measures, particularly (1) establishing seed orchards some distance from sources of coneand seed-insect populations, and (2) removing all cones and burning litter as a means of reducing such populations (Hedlin et al. 1981; Ruth 1980). The success of these two options depends on the dispersal strategies of cone and seed insects (Johnson 1962), but information on dispersal has been lacking. The purpose of this study was to obtain such information.

An undescribed microsporidium was isolated from a grasshopper species, Aulocara elliotti Thomas, in Platte County, Wyoming. A subsequent survey of grasshoppers revealed infections of the microsporidium in the other predominant grasshopper species, Psoloessa delicatula (Scudder). In a generation cycle, P. delicatula hatch in mid-summer, overwinter as late-instar nymphs, and become adults and oviposit in late spring, whereas A. elliotti diapause as eggs during winter, hatch in late spring, become adults and oviposit in early to mid-summer. The purpose of the present investigation is to report on the comparative incidence and transmission of the parasite in A. elliotti and P. delicatula.

Cochylis arthuri Dang, new species, pest of wild sunflower, Helianthus sp., from Saskatoon, Saskatchewan, is described and illustrated.

The survival of Mamestra configurata Wlk. was determined from autumn and spring samples in 1973/74, 1980/81, and 1981/82 taken from unfilled and tilled portions of 12 fields of canola (Brassica campestris L. and B. napus L.). Survival from the pre-pupal stage in the autumn to post-diapause pupae in the spring varied from 2.9 to 56.5% in unfilled soil and from 0 to 25.4% in tilled soil. In untilled soil, the variations among fields in total mortality of M. configurata were related to parasitism by Banchus flavescens and to overwintering mortality. In tilled soil, overwintering mortality accounted for most of the variability in total mortality among fields. The percentage of mortality from injury to pupae, and their disappearance following tillage, greatly increased but this type of mortality did not account for much of the variability in total mortality. The disappearance of pupae following tillage was attributed to predation. In both untilled and tilled soils, the amount of overwintering mortality was related to the depth of accumulated snow, and mortality was lower in untilled soil because the stubble trapped more snow. The survival of M. configurata was not related to soil type, the type of tillage equipment, or the frequency of tillage. The number of adults emerging from untilled and tilled soil in one field were 2.58 and 0.27/m2 for M. configurata, 5.22 and 2.85/m2 for the parasite B. flavescens, and 4.46 and 3.60/m2 for the parasite Athrycia cinerea, indicating that the survival of the parasites was less affected by tillage than that of their host.

Tillage may reduce the frequency and severity of outbreaks of M. configurata not only by increasing mortality but also by differentially affecting the survival of its main parasites.

The effects of damage by natural infestations of the flea beetles Phyllotreta cruciferae (Goeze) and Phyllotreta striolata (F.) on field plots of canola, rape (Brassica napus L.), and yellow mustard (Sinapis alba L.) are described. Damage occurred primarily during the first few weeks after emergence: seedling mortality was high during the first week and growth was reduced during at least the first 2 weeks. This early damage delayed plant development, caused unevenness in height and maturity, and reduced seed yield and raised the chlorophyll content of the seed.

Comparison among tests and treatments showed that a later-seeded test suffered less damage, and that carbofuran-treated plots were better protected than lindane-treated plots although the latter suffered slightly lower plant mortality. Yellow mustard showed a high level of resistance to flea beetle damage in comparison to rape and canola. Small differences in susceptibility were detected among three cultivars of B. napus.

The ambrosia fungus of Xylosandrus germanus (Blandford) was identified as Ambrosiella hartigii Batra and was the only fungus carried in the beetle's mycangium. This fungus and up to three species of Fusarium were isolated from walls of the beetle's galleries.