Agathis pumila (Ratzeburg) is a host-specific univoltine solitary internal braconid parasite attacking the first- and second-instar larvae of the larch case-bearer. Descriptions and illustrations of all developmental stages are given. The adults mated in the laboratory when 1-day-old females were exposed to 5-day-old males. The reproductive system of the female is discussed. The inherent fecundity is over 300 eggs and in tests at 75°F the average number of eggs laid per female was 139.8. Average longevity is 22.0 days. The average number of hosts destroyed with the ovipositor was 15.2 per female. The incubation period of the parasite’s egg was 7 days at 77°F. The attack pattern of A. pumila is described. In finding hosts the parasite was guided by chemotaxis and vibrotaxis. Longevity of honey-fed A. pumila females, without hosts, at constant temperatures ranging from 50° to 95°F was, on the average, highest at 60°F (45.6 days) and lowest at 95°F (10.6 days). Superparasitism occurs in the field and laboratory.

Evidence is presented to suggest that the gypsy moth, Porthetria dispar (L.), is numerically self-regulating through a shift in the quality of individuals induced by changes in nutrition. This qualitative change affects dispersal, behavior, developmental rate, and fecundity, and this provides P. dispar with the ability to respond to intrinsic and extrinsic factors faster and more efficiently than if dependent on selection. Adaptability is further facilitated because the change in quality can be induced either in the previous generation by the amount of nutrient reserves provided the eggs, or during the current generation by hunger, crowding, or cool temperature. This change is best characterized by an increase in the number of larvae with additional instars. In these larvae, a prolongation of instar I and a shift in behavior increases their potential for dispersal. The similarities and differences between P. dispar and Malacosoma pluviale (Dyar) are discussed.

Some aspects of the biology of the Tabanidae (e.g., seasonal distribution, relative abundance, habitat preferences, and innate host preferences) which influence the extent to which certain species are found biting various host species are discussed in relation to the tabanid population of the southern portion of Algonquin Park, Ont., Canada. Of the 36 species collected in this study, relatively few were sufficiently abundant to constitute serious pest problems.The analysis of collections of tabanids from carbon dioxide-baited traps placed in different habitat types revealed several patterns of distribution of the Algonquin Tabanidae: ubiquitous, exclusively sylvan, preferentially sylvan, riverine, and riparian species.Lists of the tabanids attracted to or biting man, moose, and white-tailed deer are presented. These lists constitute the first extensive records of the Tabanidae attracted to the Cervidae in the boreal forest region of Canada.The Chrysopinae selected smaller hosts than the Tabaninae and were severe pests of man whereas the Tabaninae were only minor pests of man but severe pests of moose. The tabanids attracted to deer presented a picture which was intermediate between that of man and moose. In addition, a few species of tabanids were unusually common on one or more hosts suggesting that some species may have innate preferences for certain hosts.

The musculature of the prothorax and the prothoracic coxa of the adult male Choristoneura fumiferana (Clem.) is described in detail and is compared with three other families of the Lepidoptera.

The fruit-tree leaf roller, Archips argyrospilus (Walker), overwinters in the egg stage. In 1969, at Kelowna, B.C., the eggs were not affected by winter temperatures of −32 °C. Eggs began to hatch during the half-inch green stage of apple bud development, and hatching was complete by the pink bud stage. Over 50% of the young larvae fed within developing buds where they were protected from direct contact with insecticides. Adults started to emerge in early June, and peak adult activity occurred during 12 June to 19 June. Only one generation was observed during the year. The first overwintering eggs were laid in early June and egg masses were numerous by the end of June.Diazinon, azinphos-methyl, and Gardona® (2-chloro-1-(2,4,5,-trichlorophenyl) vinyl dimethyl phosphate) gave seasonal control of the fruit-tree leaf roller when applied at the pink bud stage. Phosalone did not provide satisfactory control. When diazinon or azinphos-methyl was combined with oil, control was not improved and phytotoxicity occurred to the primary leaves of McIntosh and Spartan apple trees. Gardona® sprayed trees developed damaging numbers of the McDaniel spider mite, Tetranychus mcdanieli McGregor, by mid-July. None of the other treatments affected cither phytophagous or predaccous mites.

An inexpensive, artificial diet made with carrot powder, a commercially available product of Saccharomyces fragilis, ascorbic acid, mold inhibitors, and agar gave as good or better yields of G. molesta (Busck) moths as was reared from apples. One moth per 1.25 ml of medium at a cost of.08c per moth was the best obtained.

Iziphya grandipes is described and illustrated. It is a Carex-infesting species that is known only from Ontario.

A scheme for the evolution of the methods of spermatophore formation among pterygotan insects is proposed. There appear to be four methods of spermatophore formation, two male-determined and two female-determined. The male-determined methods are characteristic of the less advanced pterygotans that have fairly complex spermatophores, and the female-determined types are typical of more advanced insects in which the spermatophores are often reduced.

Behavioral differences between a Conophthorus beetle attacking jack pine shoot tips and the red pine cone beetle, C. resinosae Hopkins, were studied. In field experiments the red pine cone beetle attacked cones and shoots of both pines but preferred cones over shoots and red pine cones over jack pine cones. The jack pine tip beetle attacked both jack pine and red pine snoots, but no progeny appeared in red pine shoots. In laboratory tests, the red pine cone beetle survived equally well in vapors of simulated red and jack pine shoot resin, while the jack pine tip beetle survived best in the jack pine resin vapor. The jack pine tip beetle is described as a new species, Conophthorus banksianae McPherson.

Schistocerca gregaria possess four neurones of giant fibre proportions within the abdominal ventral nerve cord. These fibres arise from single cell bodies in the terminal ganglionic mass and pass without interruption to the metathoracic ganglion. Fibres become reduced in diameter when passing through a ganglion. Branching of the giant fibres occurs in abdominal ganglia 6 and 7.

A gelatine-based diet for rearing the onion maggot, Hylemya antiqua (Meigen), that contains sucrose, evaporated milk, yeast hydrolysate, wheat embryo, cellulose powder, n-propyl disulfide, water, and antibiotics is described. Three consecutive generations reared on this medium were equal in puparial weights, percentages of pupation, adult emergence, and egg hatch, to those reared on onion bulbs. The procedure is simple and two man-hours per week is sufficient for producing 1000 maggots daily.

Laboratory experiments indicate a diet of quaking aspen is essential to give impetus to a population increase of the large aspen tortrix. The effects of starvation and of five different host plants on larval survival, pupal weights, and adult egg potential are reported.

This paper notes further systematic changes in the lygaeid subfamily Rhyparochrominae.

A review of the literature published during the past 80 years concerning caste differentiation and caste ratios in the social Hymenoptera reveals considerable evidence that caste is determined trophogenically in the embryo (alimentary castration) rather than in the larval instars and that the caste ratios of the embryonic populations in well-established colonies are soon modified by worker action, i.e. selective cannibalization of queen-biased eggs and young larvae, in order to establish the caste ratios of the adult population that are essential to the economy of the colony.

In the summer of 1969, one year following a spray program to control spruce budworm with Phosphamidon and Sumithion in northwestern Ontario, five species of carabids and two species of lycosids were studied to assess the long term effects of insecticide spray on forest floor arthropods. For 15 weeks in the summer of 1969, beetles and spiders were almost always more numerous in the control area than in the sprayed area. Populations of the spiders and beetles are briefly discussed.

All stages of the life cycle of the midge Tanytarsus (Paratanytarsus) dissimilis Joh. were subjected to low pH and the extremes of tolerance were determined. The life cycle could not be completed below a pH of 5.5

The four Jamaican species of Cyrtinus LeConte are briefly reviewed. Cyrtinus jamaicensis n. sp. and Cyrtinus granulifrons n. sp. are described, and additional distributional records are given for Cyrtinus sandersoni Howden and Cyrtinus farri Howden.

A lectotype is designated for Lonchaea zetterstedti Becker, a holarctic species whose larvae sometimes attack bark beetles and cerambycids in conifers. The taxonomy and nomenclature of this species is clarified, its distribution and biology is discussed, and a key is provided for identification of it and its relatives.