The widespread presence of the pitch nodule maker in pine plantations and jack-pine regeneration in Manitoba and Saskatchewan stimulated this investigation. Although this insect is not causing serious damage at present it could become a problem should the area of pine plantations be increased in Manitoba and Saskatchewan.

Benomyl controlled cabbage maggot, Hylemya brassicae (Bouché), on potted cabbage plants in a greenhouse when applied as a drench 3 days or 3 hours before eggs were introduced. It was not effective when applied 2 days or more after eggs were added or when the plants were transplanted from treated to untreated soil before eggs were added. The results suggested that the action of benomyl was ovicidal.

A previous paper (Canadian Entomologist 40(2): 81–89, 1958) considered the general nature of an air-borne scent and suggested a mechanism by which a flying insect could be guided towards the source of an attractive odor. At first sight, it might seem that a repellent is merely an attractant with a minus sign, but this is an oversimplification, because an attractant may and often does bring the attracted insect in from a distance of a few miles, whereas the repellent has done its work if it removes the unwanted insect to a distance of no more than a few inches. The quantitative difference in the effect is so great as to imply a qualitative difference in the mechanism. On the naive view, the attractant draws the insect upwind and therefore the repellent should drive it downwind. A qualitative difference implies some third result, possibly a tendency to move the insect across the wind. This may, in fact, be the way repellents work in some circumstances, but it can scarcely be the whole story and is mentioned at this point merely to bring out the inherent difference between the attraction and repulsion of insects by odors.

Larval anatomy as an aid to understanding taxonomic and phylogenetic relationships of Scolytidae has been discussed in an earlier paper (Thomas, 1957). Before an appreciation of relationships can be gained, however, comparative descriptions of many species must be compiled. As representantye groups of species become available, the immature stages of genera will be described, defining characters of value in separating component entities.

Weevil damage on 12 sources of eastern white pine was measured. Differences between sources at age 13 were significant, but all sources were heavily weeviled. It is doubtful that sources resistant to the white pine weevil will be located.

Three white spruces, Picea glauca (Moench) Voss (30–35 cm diameter at breast height), felled in central Alberta, were colonized by Ips perturbatus (Eichhoff) beginning in late May 1999. The mean (±SE) density of breeding galleries on the trees was 217 ± 23/m2 (n = 30). Harem size ranged from one to four females per gallery, with a mean of 2.1 ± 0.6 (n = 90). Tunnel excavation and oviposition occurred primarily during the first 3 weeks after gallery initiation. Individual females laid 48.9 ± 2.5 eggs (n = 30) in galleries that reached 10.0 ± 0.3 cm in length (n = 45). Males assisted their mates by removing frass and woody debris from the tunnels. Males remained in their galleries for at least 1 week, although there was gradual attrition such that < 15% of males remained after 6 weeks. Large males abandoned their galleries sooner than small males. In contrast, females were present in almost half of the oviposition tunnels examined after 6 weeks, and there was no significant relationship between female size and residence time. Mortality from egg to adult was high (98%) during this 1-year study, likely a result of the intense crowding of galleries. Adult offspring were found beneath the bark in mid-July, although the main emergence did not begin until mid-September. Because such late emergence would be too late for these individuals to reproduce before winter, I conclude that I. perturbatus has only one generation per year in central Alberta.

The following descriptions have been taken from specimens in the collection of Professor James G. Needham at Cornell University. Brief diagnostic characters of each have been listed by him in his forthcoming Handbook of North American Dragonflies.

Intertidal Chironomidae (Diptera) are represented on the coast of British Columbia by Paraclunio alaskensis Coquillett and Saunderia pacificus Saunders, S. marinus Saunders, and S. clavicornis Saunders. The larvae, pupae, and adult males can now be easily identified with the aid of the new keys. The mentum of the labium was found to be an especially useful taxonomic character for the separation of the larvae of these four species.

Two deer fly species, Chrysops mitis Osten Sacken and Chrysops excitans Walker, were collected by sweep-netting around human bait on five collection dates in Algonquin Provincial Park, Ontario. Distribution patterns of the two species at two sites (abandoned airfield and Davies bog), in two habitats (open and forest edge), and at two times of day (morning and afternoon) are analysed. Chrysops excitans was more frequently collected than C. mitis. Regardless of site, both species are more common in the morning than the afternoon collections and both are more common in the open than the forest-edge habitats. Chrysops excitans was the larger species (based on wing length measurements) and its size was constant regardless of site, habitat, and time of day. In contrast, afternoon-collected C. mitis were larger than morning-collected flies at the Davies bog site. The crop contents of 241 flies were identified using thin-layer chromatography. Using melezitose and stachyose as honeydew-indicator sugars, the relative importance of homopteran honeydew and floral nectar as carbohydrate sources for these flies was determined. We found no significant differences among species, sites, habitats, or times of day. Overall, 52.8% of C. excitans and 51.1% of C. mitis had recently fed on homopteran-derived honeydew sugars, underscoring the importance of this carbohydrate source for the haematophagous Diptera.

Cyathissa quadrate, n. sp.—Ground colour creamy-white, more or less washed with luteous, the maculation black, contrasting. In type it is like that of percara, and the lines are identical in course; there is the same basal dash, and the quadrate pale blotch on the costa in median space is very similar. But there is no green shading whatever in the wing, the black markings are more intense, more contrasting, usually broader, and, in the median space, they extend below the costal pale area, shading into smoky-brown at about the middle of the wing.

Since 1934, when studies of aphids infesting potatoes were begun in New Brunswick, it has been observed that a large number of potato aphids are attacked by parasices each season. More attention was given to parasitized aphids in 1950 than in previous years, in a study of parasitism as a factor in aphid control. In this paper are recorded the parasites reared from aphids collected on potatoes and other hosts in New Brunswick in 1950.

The males of four very similar species of Macrocera are keyed and briefly described. They are grandis Lundström (Finland, U.S.S.R.), nobilis Johnson (Nearctic, widespread), summatis n. sp. (Sweden), insignis n. sp. (New Hampshire). The group of species is characterized as the nobilis group.

Female Heliothis virescens (F.) were irradiated with 7.5, 15.0, 22.5, or 30.0 krad of γ-rays and crossed with untreated males. Then the survival and fertility of the F1 insects from these crosses and the survival of the F2 descendants were studied. The F1 survival showed a dose-dependent reduction with increasing dose, but F2 survival was normal. Likewise, we found near-normal fertility in progeny from irradiated females, regardless of dose.

Two Pandemis species, introduced into British Columbia, are discussed: P. cerasana (Hübner) found in 1965 and P. heparana (Denis & Schiffermüller) found in 1978. They are compared with the native North American Pandemis pyrusana Kearfott and P. limitata (Robinson).

The genus Calotelea Westwood of the Nearctic region is revised. Ten species are recognized, all of them new to science, viz.: C. anthracina ♀ ♂ (New Mexico), C. atra ♀ ♂ (Florida), C. aurulenta ♀ (Texas, North Carolina), C. bicolor ♀ ♂ (Virginia), C. cincta ♂ (New Mexico), C. flava ♀ (Florida, North Carolina, Texas), C. lutea ♀ (Virginia), C. mellea ♀ ♂ (Georgia), C. nebulosa ♀ (Georgia, South Carolina), and C. pulla ♀ (Florida). The taxonomic concept of Calotelea is reviewed. The taxonomic position of the 10 Nearctic species is discussed and the keys to females and males given.

Intruding Oecanthus nigricornis (Walker) females stole nutritional glandular secretions from males engaged in post-copulatory behavior with their mates. This mating strategy may enhance female reproduction.

Mating behavior of Oecanthus spp. begins with elaborate male courtship involving vibratory, acoustic, and olfactory signalling. The female mounts the male, with copulation occurring soon after. During courtship and after copulation the female remains mounted and is provided with male metanotal glandular secretions. These nutritional secretions and the consumed spermatophore increase reproduction (Bell 1979; in press).

The number of new records noted in the Canadian Insect Pest Survey in 1952 was somewhat larger than usual and these and others are brought totether for convenient reference in this paper. Canadian sources of information include Survey reports submitted by officers of the Entomology and Forest Biology divisions, provincial entomologists, and other co-operators; The Canadian Insect Pest Review; Annual Report of the Entomological Sociery of Ontario; The Canadian Entomologist; Annales de l'Acfas; and Proceedings of the Entomological Society of British Columbia. A reference to the collection of the leafhopper Erythroneura flammigera (Geoffr.) on cherry in British Columbia was noted in Science News Letter, a United States publication, and details of the occurrence were obtained from H. H. Ross of the Illinois Natural History Survey.

Because little is known of the pre-settlement insect fauna of Canada it is now almost impossible to assess all of the changes that have been caused by settlement. For most of the time that has elapsed since colonization began, settlements have been small and scattered, and land use has been non-intensive. Many refuges for native insects persisted until very recently, and many still persist but are diminishing. Thus probably few aboriginal species have been driven to extinction. Many ruderal and cultivated plants accompanied settlers from Europe and Asia. Some of these provide an expanded food supply for a few native insects and these have expanded their numbers and ranges. Other native insects have been displaced and diminished by depletion of forests and planting of crops. Exotic plants are inevitably accompanied by exotic insects and Canada has provided a hospitable home for a multitude of exotic insects. Over 300 species have been deliberately introduced for biological control.

Once established in a colonial environment, the exotic origins of immigrant species are difficult to detect. Seven criteria for detecting exotic insect populations are suggested.

The impacts of settlement on the principal geographic regions of Canada and their probable influence on insect faunas are briefly discussed.

It is concluded that the insect fauna of Canada has been greatly enhanced by settlement.

A field trial with toxic-bait blocks for suppression of subterranean termite activity was initiated in Toronto. Decayed, mirex-impregnated red pine wood blocks 2.5 × 3.8 × 0.5 cm were placed individually in soil at 1.5-m intervals. Attack on bait blocks effectively suppressed termite activity for 3 years in the eight plots. The method offers a cheaper, environmentally sound, effective alternative to conventional soil-poisoning methods.

Hemlock sawfly infestations occur most commonly in the warm southern half of southeast Alaska. Biotic factors that limit sawfly populations are a fungus, Entomophthora sphaerosperma, which kills disproportionately large numbers of female larvae; food quality as affected by host site and defoliation; and three ichneumonid parasitoid species, Delomerista japonica diprionis, Oresbius tsugae tsugae, and Itoplectis quadricingulatus, which attack prepupal larvae in cocoons. E. sphaerosperma was the most effective natural control in recent years, especially during wetter than normal summers. Parasites which attack after the fungus has decimated larval populations were most abundant during two dry summers. Parasitization and sawfly emergence were directly related, and both were highly inversely correlated with percentage fungus killed sawflies. Sawflies reared on lightly defoliated trees produced significantly more eggs than those reared on heavily defoliated trees, and fecundity was directly related to cumulative heat units during the summer. Between 1952 and 1974, most negative sawfly population trends south of Frederick Sound occurred when two wet summers occurred consecutively. Apparent widespread collapse of sawfly populations in 1974 was associated with low temperatures in 1973 which delayed sawfly development and reduced opportunities for successful oviposition.