Mites of the genus Phytoseius Ribaga largely inhabit plants and are at least partly predacious, feeding on tetranychid, eriophyid, and other mites. They probably also feed on pollen, honeydew, and plant juices, as do other phytoseiids that have been studied (Chant 1959; Dosse 1961; McMurty and Scriven 1964). They are not usually found in soil or humus but occur on many kinds of low growing plants as well as coniferous and deciduous trees. They have been collected on all continents and from the arctic to the tropics.

Access to drinking water increased the longevity of Coccinella trifasciata perplexa Muls. by about 35%. The water content of field-collected insects was 70% and of laboratory-fed insects 64%. Rate of loss of water increased, and longevity decreased when protein was absent from the food.

Anatis mali Auct. lived more than 1000 days and Coleomegilla maculata lengi Timberlake lived more than 400 days when fed on various synthetic foods. Seven of 13 species tested kid eggs when fed on these foods. A diet containing desiccated liver was the best non-prey food supplement for reproduction, and adults of three generations of C. maculata were kept on this food.

A. mali preferred dry powdered pea aphids, Acyrthosiphon pisum (Harr.), to either bean aphids. Aphis fabae Scop., or corn aphids, Rhopalosiphum maidis (Fitch), whereas C. maculata preferred corn pollen to aphids and A. pisum and R. maidis to A. fabae. Previous feeding did not affect the preference of either A. mali or C. maculata for dry aphids or pollen. C. maculata produced six eggs per mg. of food while feeding on A. pisum and four on R. maidis. Young adults ate more than older adults.

The rate of food intake was highest in A. mali during the first two weeks and in C. maculata during the first eight days after emergence. The living weight and dry weight of feeding C. maculata adults increased for eight days and then did not vary, whereas the water content decreased in this period. The index of relative growth was about 0.10 mg. per day per mg. of adult weight and food efficiency was about 0.18 mg. per mg. of food.

The mallophagan genus Aquanirmus, parasitic on grebes (Podicipidae), is revised. Four new species and one new subspecies are described: emersoni ex Podiceps grisegena, occidentalis ex Aechmophorus occidentalis, podilymbus ex Podilymbus podiceps, bucomfishi ex Podiceps auritus, and bahli chamberlini ex Poliocephalus dominicus. The geographic and host distributions of the parasites are discussed. It is pointed out that geography plays an important role in the distribution of the species of Aquanirmus.

Laboratory tests revealed that female Douglas-fir beetles, Dendroctonus pseudotsugae Hopkins, boring in logs of both host and non-host species produce a volatile substance that both attracts and arrests adult beetles. Male arrestment provided a reliable method for laboratory bioassay of volatile substances. Field tests were devised to show the attack, the attraction produced, and the broad development in six tree species: Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco; western larch, Larix occidentalis Nutt.; ponderosa pine, Pinus ponderosa Laws.; western hemlock, Tsuga heteropbylla (Raf.) Sarg.; western white pine, Pinus monticola Dougl.; and grand fir, Abies grandis (Dougl.) Lindl.

Lipids account for approximately eight per cent of the wet weight of Neodiprion pratti larvae. Fatty acids comprise eighty per cent of the total lipids. Approximately seventy-five per cent of the fatty acids are unsaturated and over seventy per cent have eighteen carbons. Four unknowns were characterized as being polyunsaturates of sixteen and eighteen carbons.

A lightweight, economical container used for long-distance shipment of adult Hymenopterous parasites of the Siricidae, and their hosts, is described. Survival of 94.8 per cent of insects in transit is reported.

The new cuticle is secreted around the old tentorium which breaks into four pieces. These pieces are withdrawn through the tentorial pits at the moult.

In population studies of the pine leaf adelgid, sampling techniques are required. Procedures for sampling galls on spruce and for associated adelgid stages are described. Gall distributions both within trees and between trees are non-random, following the negative-binomial series. Aggregation within trees arises from a disproportionate number of galls occurring on the upper crown branches. Between trees, gall populations are more dense on the larger trees, and red spruce is more heavily infested where red spruce and black spruce are mixed. The proposed sampling unit is composed of one branch from each of the upper two vertical crown quarters, and one longitudinally halved branch from each of the lower crown quarters. The examination of sample units from 50 trees will provide a reliable estimate of stand populations except where low gall densities or heterogeneous spruce stands make a larger sample mandatory. Additional details of sampling and the biological significance of the findings are discussed.

The pine gall weevil has a 3-year life cycle on red pine (Pinus resinosa Ait.) in Michigan. Adults oviposit from June to August, depositing 1 to 10 eggs in a niche chewed in the bark of a branch internode. Larvae first emerge in August, feed as a group toward the cambium, and then radiate out along the xylem. Head capsule measurements from 1585 larvae indicate that there are three larval instars. Gall development begins in June of the second year, shortly after the larvae begin the second instar. The third instar commences in June of the third year. Pupation occurs in May of the fourth season; adult emergence follows in June. Overwintering occurs in the egg stage or in the three larval instars. Adults do not overwinter, and apparently three distinct broods occur in Michigan.

Reproductive rate of the parasite Nasonia vitripennis (Walk.) on pupae of the housefly, Musca domestica L., measured by the number of mature progeny produced per female in 18 hours, decreased with increasing parasite:host ratios. This decrease resulted partly because each female laid fewer eggs, and partly because of increased larval mortality caused by superparasitism. The average number of eggs laid per female was reduced because the parasites wasted relatively more time drilling into unsuitable (i.e. parasitized and previously drilled) hosts on which they subsequently laid few or no eggs; and because the females interfered more with each other while ovipositing. Incidence of superparasitism was greater at higher parasite:host ratios because, in spite of increased interference among the females, there were more simultaneous attacks by two or more females on each fly pupa.

Measurements of the supercooling points of eggs from different latitudes suggest that the cold-hardiness of N. sertifer is increased by the selective pressure of low winter temperatures. In Ontario, the insect is only beginning to experience temperatures capable of influencing population trends, but the selection of a more cold-hardy population may be in progress. It is predicted that this insect will eventually be capable of extendng its range into natural stands of jack pine in the northwestern portion of the province.

Overwintering eggs are inherently able to supercool to about −26 °C., but exposure to certain non-lethal conditioning temperatures increases their cold-hardiness. Increased cold-hardiness apparently is associated with the appearance of glycerol in the eggs. Mortality curves based on supercooling points of eggs exposed to optimal conditioning temperatures are useful in predicting overwintering mortality of eggs that are not protected by snow cover.

In the laboratory 90.7% of both sexes of moths of the pale western cutworm, Agrotis orthogonia Morrison, emerged from pupae between noon and midnight; almost half emerged between 2 and 4 p.m. Mating, evidenced by spermatophores in the bursa copulatrix, occurred almost always at night, within 3 days of emergence, and at temperatures between 5 and 35 °C. Most females mated only once. Multiple matings, with a maximum of 3 times, occurred in less than 20% of females. Males mated with a maximum of three females. Eggs developed during the pupal stage and were ready for fertilization when the moths emerged. Oviposition began on the first or second day after mating, peaked soon after, and continued until just prior to death of females. Maximum oviposition by one female was 564 eggs, with means from 90 to 342. Oviposition occurred at all temperatures from 5 to 35 °C. with an optimum between 10 and 25 °C. More eggs were laid in the dark or in subdued light than in continuous bright light. Females when unfed could oviposit but when fed water or sugar solutions they laid more eggs. Longevity varied directly with feeding and inversely with temperature. Mean longevity of moths fed honey solution in the laboratory was 12 days for both sexes. A diurnal rhythm of oviposition occurred with distinct peaks; 80% or more of the eggs were laid between noon and early evening. Rhythm of oviposition was apparently initiated by light and could be reversed by reciprocal light regimens but was maintained in continuous dark or light. The maximum distance flown on a flight mill was 14.7 miles for males and 3.5 miles for females. Speed varied from less than 1 to almost 3 m.p.h.

When the polyphagous parasite Itoplectis conquisitor (Say) was reared on either of two hosts, Thymelicus lineola (Ochs.) or Galleria mellonella L., it showed no preference for the host from which it had emerged when exposed to equal numbers of the two hosts in the same type of ecological niche. No evidence for the existence of preimaginal conditioning in I. conquisitor was obtained.

The existence of a chemical female sex pheromone in the Oriental fruit moth has been demonstrated; it both attracts and sexually excites adult males. Males without antennae are neither attracted to, nor sexually stimulated by, the pheromone. Thus, the pheromone appears to be essential for reproduction. Active pheromone can be extracted with benzene from the tips of virgin female abdomens and bioassayed with males. The gland believed to produce the pheromone was located and examined histologically. It is now possible to investigate the chemical nature of the pheromone and its possible use in the control of the Oriental fruit moth.