A detailed taxonomic definition of the family Ironomyiidae is presented, based on both sexes of Ironomyia nigromaculata White, the only known representative. Attention is drawn to the peculiar blend of primitive and specialized conditions displayed by this species. Most of the characters discussed are illustrated and compared with homologous characters in hybotine Empididae, Platypezidae, and other groups.

A total of 6995 summer generation Ips confusus (LeConte) adults was reared from logs of Pinus ponderosa Laws. under laboratory conditions. Emerging adults were collected every two hours throughout the day and their sex determined. Females predominated for the first eight days but the sex ratio at the end of 40 days was 1.18 ♀, ♀: 1 ♂. High differential loss of males before reproduction is discussed. From logs attacked in the spring 62.0% of the parent adults re-emerged. Large numbers of such parents capable of reproduction could greatly increase the severity of an infestation. Spring brood emergence totaled 67.64 beetles per sq. ft. of bark surface, while summer brood emergences from two different areas were 54.50 and 33.37 beetles per sq. ft. Above 72° F., peak male emergence occurs at the 10:00 a.m. or noon collection. Females exhibit a lesser peak in mid to late morning and a major peak in mid to late afternoon, but at temperatures below 72° F. a unimodal female emergence curve becomes apparent.

The effect of temperatures on the development of a virus disease of Neodiprion swainei Midd. was studied at constant temperatures of 30° and 12 °C., and under fluctuating temperatures (15°–20 °C.) in the laboratory and outdoors. Viral concentrations of 30 × 106 polyhedra per ml. and 1 × 106 polyhedra per ml. were used. Only the higher concentration of virus was effective at 30 °C. At 12 °C. the incubation period of the disease was prolonged and mortality caused by the virus was considerably reduced for both viral concentrations. Mortality due to the virus was similar at both viral concentrations for the fluctuating temperatures which were within the optimum temperature range for larval development.

Female pupae of Malacosoma pluviale (Dyar) treated externally with 80 μl of farnesyl methyl ether during their second day retained most of their original lipid content on the seventh day, when the eggs were maturing. Control pupae lost nearly half their original score in the same interval. In contrast to controls, pupae treated with 40–80 μl (4th–6th days) developed fewer, lighter eggs, and their adults lived longer, were more active, and less inhibited in egg-laying. But the egg masses from treated individuals contained scattered, tumbled eggs and were oversupplied with spumaline.

When eggs were incubated in April, those from individuals treated with ≥ 40 µl failed to hatch. Eggs from females that had received < 40 μl hatched, bur the resulting colonies died before their second instar in their normal habitat, whereas control colonies survived. Hatching of treated stock could be induced by premature incubation in January, but the numbers and quality of the emerging larvae were greatly reduced in comparison with controls.

The results provide further evidence that behavioral types in M. pluviale are mainly nutritional products. Because of the treatment, developing eggs were deprived of nutrients during the pupal stage and developing adult tissues were oversupplied. Farnesyl methyl ether may have exerted its effect by acting like an excess of juvenile hormone during that part of the pupal stage in which the normal level of activity of the true juvenile hormone is thought to be very low.

Field evidence suggests that an equivalent humoral imbalance sometimes may occur naturally, and thus affect a generation's reproductive capacity, especially near a peak in abundance. Hormonal mimics therefore might be used to manipulate pest populations, but this suggestion includes a cautionary note.

The pine seedworm, Laspeyresia piperana (Kft.), is a common pest in cones of Pinus ponderosa Laws. in British Columbia and may destroy up to 50% of the seed.

Moths emerge in May, mate, and lay eggs on second-year pine cones. Immediately after hatching, the larvae migrate to the centre of the cone and feed on seeds throughout the summer. In autumn, larvae tunnel into the cone axis to overwinter. Pupation occurs in spring.

The effectiveness of incandescent and cool white and black light fluorescent lamps was compared in traps used to sample biting midges, mainly Culicoides sanguisuga (Coq.), around Lac Serpent, Quebec, between 17 June and 31 July 1966. The ratio of the modified geometric mean nightly catches of the lamps was about 1:1:40, respectively. A New Jersey trap with a fluorescent black light is highly effective, and to some extent selective, for Culicoides spp.

Five species of the genus are discussed and illustrated, including a new species, C. occidentalis from Pelecanus occidentalis. The lectotype is designated for C. unciferum Kellogg, fixing the type-host as Pelecanus erythrorhynchos. A key is given to the species.

The two-spotted spider mite, Tetranychus urticae Koch, showed a pronounced two-peak diel periodicity of susceptibility to dicofol, in a natural regimen of light: dark. The first occurred between 0200 and 0500 hours and the second between 1300 and 1800 hours. Mortality dropped sharply after sunrise (0441 hours) and again an hour before sunset (2002 hours). Lowest mortality occurred near midday. Egg-laying was inversely related to mortality over the 24-hour period.

Head capsule measurements of the ambrosia beetle Xyloterinus politus (Say) revealed three larval instars. The xylomycetophagous larvae lengthened their cradles and a positive correlation existed between head width and cradle length. A sex factor of 0.84 was in favor of the female adults. Dissection of active galleries revealed only a single female per gallery. Males were never seen to initiate or excavate a gallery and were forced from the entrance hole by the female when placed in an active attack. The gallery system studied was simple, the entrance hole penetrated into the sapwood for a variable distance before it branched into secondary tunnels at right angles to the main gallery.

Eggs were laid singly in cup-shaped cradles excavated by the female. The cradle openings were plugged with frass throughout the duration of the immature stages. Callow adults emerged from the cradles by forcing the frass plug covering the entrance, and re-entered, their position reversed to feed upon the ambrosial fungus growing on the cradle walk X. politus overwintered as an adult in the old cradles and galleries. Larvae of Ipideurytoma sp. (Hymenoptera: Eurytomidae), probably a larval parasite of X. politus, were found in cradles.

Insect eggs and small organisms may be removed from foliage or bark with solvents and recovered on filter paper. Tests with Acleris variana (Fern.) showed that 96 per cent of eggs were recovered compared to 47–70 per cent counted on foliage. Tests indicated that the extraction method required one-third to one-tenth the time spent in counting the organisms on foliage. The extraction method was more consistent than counts on foliage, and less affected by differences in personnel and working conditions. The method and the solvent must be selected and modified to suit the organism.

The orientation of Aedes aegypti in an upward or downward vertical air current was studied. The vertical movements of A. aegypti which have been activated by CO2 are always against the air flow and toward the inlet end, where the insects alight and probe. With sufficient illumination A. aegypti locate an invisible artificial host whether it is at the top with air moving down or at the bottom with air moving up. They do not attempt to locate a visible, black, artificial host placed downstream. Body attitude is similar in upward or downward air flow. The mosquitoes follow the vertical movement of a surrounding spiral stripe pattern, whether stripe movement is upward or downward, whether air is still or moving vertically with or against the stripes. They will not fly against stripe movement to reach an upstream host, real or artificial. Repellent vapor destroys the upstream orientation when air flow is vertical but not when the flow is horizontal. The stripe-following action is not affected by repellent. The experiments indicate that A. aegypti possesses a vertical-air-speed sensor, of a mechanical type, to direct movement up or down in a vertical air stream. The cybernetic system must be complex and requires cooperative use of mechanical and optical sensory information channels. The initial action of repellent vapor appears to be peripheral rather than central to the nervous system, and to affect only the mechano-, chemo-, and thermo-receptors.

Inferences regarding the value of Nasonia vitripennis in the natural control of Musca domestica based on laboratory research should consider the general absence of this parasite on that host in nature. Predominant natural parasites of M. domestica are listed.

For maturation feeding, the teneral adults of Pseudohylesinus nebulosus (LeConte) infest healthy twigs of Douglas-fir trees, where they excavate short, irregular galleries in the wood. Mechanically damaged twigs and smaller branches then break off, or a canker-like structure, vulnerable to further breakage, develops at the place of feeding. Some silvicultural and forest entomological implications are mentioned.

Olesicampe (Holocremnus) sp. nr. nematorum (Tschek) has become established at two locations in Manitoba, and has built up rapidly in both. In 1965 at Pine Falls, where it was released in 1961, 61% of the hosts were parasitized in the vicinity of the release point, and at Riverton, where it was released in 1962–1963, 87% were parasitized. A number of characteristics seem to endow this parasite with a marked ability to act against the larch sawfly. These include good synchronization, longevity and searching capacity; low superparasitism; absence of hyperparasitism, and lack of host resistance by encapsulation. O. sp. nr. nematorum has dispersed at least one mile at Riverton and one-half mile at Pine Falls. The percentage parasitism decreases rapidly from the release points to these limits.

The construction of a portable and durable knockdown-type cage, designed for rearing larch sawfly larvae in the field, is described.

Queen losses were compared when caged queens with attendant worker bees and caged queens without attendants were used in packages of honey bees being shipped from the southern United States to Canada. When the colonies were hived there was no difference in queen losses in the two treatments.

Chrysocharis laricinellae (Ratz.) mated readily in the laboratory when several individuals of both sexes were held together in a vial. The courtship dance performed by the male is described. Parasite females develop mature eggs 3 days after emergence and are apparently capable of resorbing the eggs if hosts are not available, and to produce new ones after host-feeding. Storage of eggs in the ovary for 5 months at 55°F and sterility (phasic castration) of certain individuals is reported. Longevity of egg-laying females at 75°F was about 1 month less than that of parasites that had been denied contact with hosts. Odor apparently plays little or no role in the location of the larch casebearer larvae by C. laricinellae, but chemical surface stimuli seem to exist on the surface of a mine or case of Coleophora laricella (Hbn.). The parasite is also stimulated by vibrations of the host in its case. The oviposition and host-feeding pattern of C. laricinellae is described. Host-feeding on fourth-instar larvae of the larch casebearer contributed little to host mortality.

Leaf-miners associated with common cultivated plants are especially liable to become esrahlished in new areas through transportation with their hosts, and this possibility should always be considered when the agrommyzids of poorly-known faunal regions are studied, so that redescription of such species as new forms may he avoided. One of the species here recorded for thc first time from both Chile and Easter Island is a case in point. Phytobia maculosa (Malloch), known as a leaf-miner in cultivated Chrysanthemum in the U.S.A. since 1896 (though not correctly recognized and described until 1913), has since been redescribed from the same host plant in southern Brazil. Its known hosts now include 13 genera of Compositae and it is evidently widespread in the U.S.A., in the West Indies, and in temperate South America. It also occurs in Hawaii. Although not so far reported in Canada it almost certainly will be found in southern Ontario and British Columbia. Horticulture, both private and commercial, must have greatly assisted its spread in North America and elsewhere.