The suitability of four indigenous species (Descurainia pinnata (Walt.) Britt., D. richardsonii (Sweet) O.E. Schulz, Lepidium densiflorum Schrad., and Rorippa palustris (L.) Besser) and one introduced species (Erysimum cheiranthoides L.) of Cruciferae as host plants for the larvae of the red turnip beetle, Entomoscelis americana Brown, was tested in the laboratory using excised true leaves as food and Brassica napus L. and D. sophia (L.) Webb as control treatments. R. palustris was a suitable food plant. D. pinnata, D. richardsonii, E. cheiranthoides, and L. densiflorum were marginally suitable. Of the four indigenous species, R. palustris probably is the only one that normally is a host plant of the larvae in nature.

All stages of Cricotopus (Isocladius) myriophylli n. sp. are described and differentiated from those of other members of the sylvestris group of Cricotopus van der Wulp. The larval diagnosis for the sylvestris group is emended.

A new genus of Gonianotini, Spinigernotus, is described with Sphragisticus simulatus Barber 1918 as type-species. S. simulatus, known only from New Mexico, is reported from Mexico. The new genus Cordillonotus, and type-species C. stellatus, are described from British Columbia, California, Oregon, and Washington. Cordillonotus is tentatively placed in the tribe Rhyparochromini.

The last-instar larvae of 22 species of Spilomelini are described and illustrated. Diagnostic characters are given, and a key included, for North American species.

The larvae of Rhinocyllus conicus Froel. feed within the flowerheads of Carduus nutans by tunneling through callus that appears near feeding sites, by forming chambers of callus beneath developing florets, or by tunneling within pith of the peduncle. The induction of callus by R. conicus is a gall-like response providing the larvae with additional nutriment and a shelter. Callus formation also reduces plant resources destined for developing additional flowerheads.

Four lepidopterous and sawfly species were collected from Lonicera (honeysuckle) in the Ottawa area and reared for hymenopterous parasites. The following new species are described here, with new host records: Triclistus xylostellae n. sp. (Ichneumonidae, Metopiinae) from Plutella xylostella (Linnaeus) (Lepidoptera, Plutellidae), Copidosoma glandiferellae n. sp. (Chalcidoidea, Encyrtidae) from Deltophora glandiferella (Zeller) (Lepidoptera, Gelechiidae). The following are new host records: Mesochorus vittator (Zetterstedt) (Ichneumonidae, Mesochorinae) hyperparasitic in Olesicampe lophyri (Riley) (Ichneumonidae, Campopleginae) from Zaraea americana Cresson (Hymenoptera, Cimbicidae), Oncophanes americanus (Weed) (Braconidae) from D. glandiferella. The following are parasitic species with lepidopterous hosts already recorded: Apophua simplicipes (Cresson) (Ichneumonidae, Banchinae) and Macrocentrus iridescens French (Braconidae), both on Choristoneura rosaceana (Harris) (Lepidoptera, Tortricidae). The cephalic structures of the final-instar larvae of the following species are described: T. xylostellae n. sp., M. vittator, and A. simplicipes.

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.

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.

In the field in Europe, Lenta cyanella (L.) has been reported to breed only on Canada thistle (Cirsium arvense (L.) Scop.) whereas in the laboratory it breeds on species in the genera Cirsium, Carduus, and Silybum. In one laboratory choice test, L. cyanella preferred Cirsium drummondii T.&G. over Canada thistle. In one field-cage test, it concentrated feeding and oviposition on one C. drummondii which thrived in preference to three other C. drummondii and Canada thistle which grew poorly. In a second field-cage test, Canada thistle predominated and L. cyanella fed and oviposited most on Canada thistle although its intrinsic preference for C. drummondii was still apparent. A review of the field host-plants of three accidentally introduced thistle-feeding insects, Orellia ruficauda (F.), Cleonus piger Scop, and Cassida rubiginosa Müller, and the introduced biocontrol agent Rhinocyllus conicus Froel., showed that these insects, which have a wider range of hosts than has L. cyanella, concentrate breeding on introduced species of Cynareae (Compositae). Based on this evidence, it is extrapolated that L. cyanella will exploit Canada thistle and will not damage populations of native Cirsium species when established in North America.

Both adult females and larvae of Agromyza frontella (Rondani) exploit the same food source, alfalfa leaflets. In laboratory studies, larval development in leaflets with many adult nutrition holes resulted in a higher incidence of mortality than in leaflets with low levels of adult feeding. Furthermore, in heavily attacked leaflets, survivors had a slightly longer larval developmental time and lower pupal weights. In heavily attacked alfalfa fields where adult nutrition holes are numerous, the above-mentioned adult–larval interaction could play a density-dependent role in the population dynamics of A. frontella. However, in most situations adult feeding probably has an indirect effect, accentuating intraspecific larval competition by decreasing the quantity of the available limiting resource.

The posterior midgut of a seed-feeding pentatomid, Euschistus euschistoides (Vollenhoven), contains the proteinases cathepsin B and aminopeptidase. Cadiepsin B hydrolysis of benzoyl-DL-arginine-2-naphthylamide is activated by thiol chemicals and EDTA. Aminopeptidase hydrolysis of leucine-p-nitroanilide is activated by MgCl2 and inhibited by cysteine, glutathione, EDTA, and CaCl2. These results are similar to those obtained for cathepsin B and aminopeptidase from blood-feeding Hemiptera and support the hypothesis that catheptic proteinases are unique to this order.

The female-produced sex pheromone Cheimophila salicella (Hbn.) was found to be a mixture of E-11-tetradecenyl acetate, E-11-tetradecen-1-ol, tetradecyl acetate and E-11-tetradecenal, as determined by chemical analyses and field-trapping results. Capillary gas-liquid chromatography of individual female tip washes indicated relative ratios of 100:15:10:2. Field-trapping experiments showed the E-11 acetate to be essential and the E-11 aldehyde to be a powerful synergist for trapping of male moths.

Wheat treated with 2,4, or 8 ppm of insecticide, on a whole-seed basis, was bioassayed with Tribolium castaneum (Herbst) and Cryptolestes ferrugineus (Stephens) adults at 30 °C and 70% RH after 4 days, 2 weeks, and then at eleven 1-month intervals. Malathion was more toxic to C. ferrugineus than to T. castaneum whereas the reverse was true for pirimiphos-methyl; malathion showed little effectiveness after 2 weeks. The pyrethroids, cypermethrin and permethrin, were more toxic to T. castaneum than to C. ferrugineus. For malathion and pirimiphos-methyl, percentage knockdown of the insects following exposure for 24 h was similar to percentage mortality after a 3-day recovery period; for cypermethrin and permethrin under the same conditions, knockdown was consistently greater than mortality. Cypermethrin at 8 ppm on wheat gave 90% knockdown of T. castaneum after 1 year of storage. Pirimiphos-methyl gave nearly 100% control of both species for 9 months at 4 ppm and 11 months at 8 ppm, and of the grain mite Acarus siro (L.) for at least 4 weeks at 8 ppm. Seed germination did not change during 1 year of storage; the levels of Penicillium spp. infection observed were much greater (about 60%) on wheat treated with pirimiphos-methyl (2, 4, 8 ppm) or cypermethrin (2 ppm) than with malathion or permethrin.

Adults of the new species Cubanotyphlus largo Frank, from Florida, U.S.A., are described, illustrated, and differentiated from adults of C. jimenezi Coiffait and Decou and of C. poeyi Decou, which are known only from Cuba. Distinguishing characteristics of Cubanotyphlus and of the 12 other described genera of New World Neotyphlini are given in a table, as are bibliographic citations and distribution of the 39 known species of New World Leptotyphlinae. The habitat of C. largo in the northern part of Key Largo, Monroe Co., Florida has been threatened by encroaching urban development but recently has been listed for acquisition and conservation by the government of Florida.

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.

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 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.

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.