A study of the ant populations was made through a transect of mid-continent North America from Churchill on Hudson Bay and various localities around the Great Lakes to Iowa and northern Illinois. Data were obtained from extensive personal collecting and from literature sources. The results were assembled and discussed within an ecological framework provided by Merriam’s life zones, and showed a regular diminution in the variety and wealth of the ant faunas progressing from south to north. Though the number of species at Churchill is extremely reduced, ants nevertheless do occur there as established reproducing colonies, even in the presumed tundra habitats. These forms which exist so far north represent a highly impoverished remnant of richer faunas further south. Although none of the species is peculiar to the area, each must be tolerant of high boreal environments. A total of 135 species and subspecies are listed for the Carolinian and Alleghenian zones combined, 43 taxa for the Canadian Zone, 4 taxa for the Hudsonian Zone, and 4 also for the Arctic Zone. Comparisons with the recorded ant faunas of the Rocky Mountains of Colorado were made with respect to the corresponding zones, namely, the Plains (Upper Sonoran), Foothills or Submontane (Transition), Montane (Canadian), Subalpine (Hudsonian), and Alpine (Arctic) zones, and appropriate similarities and differences noted.

Parathion was the most effective ovicide for European corn borer eggs. Six other materials gave at least 50% mortality at 100 p.p.m., but 17 had little or no activity. Corn borer larvae were more susceptible to insecticides, and probit-mortality data was determined for 17 materials.

In 1970 and 1971 heavy populations of borer were controlled on sweet corn and peppers by twice-weekly sprays of carbaryl, Lannate, and Phosvel. Furadan applied weekly provided good control, and several of the experimental compounds were effective.

Dactynotus nodulus is described and illustrated and its affinities noted.

A list is given of 32 species of aphids, with their host plants, from Thailand. Males and oviparae of Aphis craccivora Koch, a male of Rhopalosiphum maidis (Fitch), and an ovipara of Tinocallis kahawaluokalani (Kirkaldy) were collected. Tritrichosiphum thailandicum new genus, new species is described.

This deals with the distributions of Papilio machaon L., Oeneis chryxus strigulosa McD., and Boloria napaea Hoff., as correlated with the basic geological formations to which they are evidently restricted.

Adult apple maggots, Rhagoletis pomonella (Walsh), were relatively free from attacks by predators in southern Ontario. The main reason for this was the flies’ alert avoidance of approaching objects. In addition to this protection from predators, the flies appeared to be avoided by hunting spiders. Adults of the cherry fruit fly, Rhagoletis cinqulata (Loew), were equally alert and apparently free from predation while they were in apple trees.

Seventeen species of parasitic Hymenoptera were found associated with balsam gall midge in Maine. Tetrastichus marcovitchi (Cwfd.), Tetrastichus sp. near solidaginis Burks, Plalygaster mainensis MacG. and Osgd., and P. abicollis MacG. and Osgd. were the most abundant known parasites, while several other species, some of uncertain status, were less frequently encountered. A key is presented for commonly encountered species, and details of the life histories are given for important midge parasites.

Parasitoid populations were sampled before, and for 4 years following, an aerial application of the insecticide phosphamidon to control a sawfly outbreak. Adult parasitoid mortality was high because of spraying, but a reservoir of parasitoids in host cocoons remained to repopulate the treated areas. In moister sites the number of species decreased and their relative abundance changed, but moderate numbers of parasitoids remained 4 years after spraying. In a dry site with little ground vegetation, none of the species present before spraying remained by the fourth year.

Measurements of head capsule lengths and widths show that Tipula paludosa Meig. larvae have four instars. The shape and size of the mandibles and labia are good characters for differentiating the instars.

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.

Three species of two genera in the family Ceratopogonidae, namely Culicoides obsoletus Meigen, Culicoides yukonensis Hoffman, and Dasyhelea sp. near tristyla Wirth were collected from the area near Fort McMurray, Alta. (lat. 56°44′ N., long. 111°23′ W.). The order of abundance of the three species was C. obsoletus, C. yukonensis, and Dasyhelea sp. C. obsoletus and C. yukonensis were most active during the evening hours and Dasyhelea sp. was most active during daytime hours. Both species of Culicoides were serious pests of humans and animals in the community.

Predation by birds and social wasps (Vespula spp.) on larval colonies of Hyphantria cunea Drury was studied in both natural and artificial populations, and predation by mammals on overwintering pupae in the ground was studied in artificial populations. The species of predators are listed and some important differences in their habits of attack are described. Per cent predation by birds is directly related to the population density of H. cunea over a range of densities, but inversely related after density exceeds this range. When habitat and weather favor rapid population growth, H. cunea "escapes" from the population range in which predation exerts a regulatory influence.

The effects on the house fly, Musca domestica (L.), of a series of cis-9 alkenes containing 19–25 carbon atoms were investigated. An unexpectedly wide spectrum of these homologous hydrocarbons showed biological activity. Synergism and interesting changes in behavioural responses (excitement, mating, and orientation) varying with structure and concentration were observed.

On the basis of data obtained during a light-trapping survey in western North America, noctuid moth activity appears to be influenced by nightly temperatures but not by lunar periodicity.

Carbofuran was applied to three hayfields at a rate of 0.56 kg/ha in early June. This caused significant reductions of Thysanoptera, phytophagous Coleoptera larvae (including the alfalfa weevil, Hypera postica (Gyl.)), and Cicadellidae. It caused similar reductions in Araneida and parasitoids. The differences between treated and untreated plots were no longer significant by September. Carbofuran did not significantly affect the yield of air-dried hay or of crude protein.

Comparative gas chromatographic analyses of volatiles generated by Ips indicate the presence of cis- and trans-verbenol in hindguts of the 12 species investigated. The biosynthesis of verbenol does not require feeding, but instead results from the insect’s contact with oleoresin. Ipsdienol is the most frequently occurring pheromone in Ips species after feeding. Aggregation of these bark beetles appears to be regulated by two distinct functional types of pheromones, i.e. contact pheromones, produced and/or released upon contact with new host material, and frass pheromones, which require actual feeding in the new host’s tissues. The aggregation of aggressive bark beetle species seems to be largely dependent on contact pheromones, whereas the host’s susceptibility to feeding is indicated by the release of frass pheromones.

Triglycerides of Nigrospora sphaerica which elicit aggregation of adult confused flour beetles were separated according to their degree of unsaturation by chromatographic methods. Several fractions showed activity. The largest and most active fraction consisted of monounsaturated triglycerides of which the major component was oleodipalmitin. Triglycerides from three other fungi showed varied levels of activity.

Larvae of Leptinotarsa decemlineata (Say) reared on tomato fed longer, consumed more foliage, and had a lower survival rate than when reared on potato, its principal host. On both plants, a direct linear relationship was obtained between food consumption and larval growth. Potato was the more efficient of the two plants in terms of food conversion to body matter. This was reflected by increased weight gain of the larvae and greater pupal size.

Adults from larvae reared on tomato were smaller and less fecund than those from larvae reared on potato. Half of them rejected tomato as food. However, egg-laying increased when they were transferred to potato after 50 days. The present investigation indicates that L. decemlineata can survive and attain maturity on tomato in the absence of its principal host plant. However, when potato is once again available, it is able to increase growth, accelerate development, and achieve a greater reproductive potential.