The V. arenaria queen was able to heat her nest shortly after it was constructed, and expended up to 550 cal per hour per gram of biomass to accomplish this. In contrast, the V. maculata colony was not heated until it was 11 days old, by which time the brood consisted of about 15–20 large larvae which probably played a major role in the heat production process. When both colonies were about 2 weeks old, energy expenditures of more than 400 cal/h could be maintained for several hours, and the nest temperature could be elevated as much as 4°C above the ambient. During these periods the larvae probably accounted for as much as 66–71% of this energy expenditure. In addition to playing an active role in heating the nest, the larvae apparently provide the queen with a food source while she is producing heat during non-foraging periods.

The myzaphidines in Canada consist of three genera and seven species of which two are described as new. Myzaphis v. d. G. is recorded from North America apparently for the first time and one endemic species is described. Keys and brief descriptions of the genera and viviparous forms are offered. Pentatrichopus Borner, which includes the economically important pests of strawberries is considered a synonym of Chaetosiphon Mord. Chaetosiphon is retained as a genus only because of its association with Rosa spp., Potentilla spp., and Fragaria spp. The presence of five setae on the basal tarsal segments, which was the only means by which the myzaphidines could be distinguished from other capitophorine aphids, is no longer valid. C. fragaefolii, which has been considered to be a complex of two species, is treated as a single species. The conspicuous variation in the arrangement of dorsal abdominal setae and in the tarsal setae is readily explained by neotenic development which probably only indirectly affects the development of the setae.

The larch sawfly, Pristiphora erichsonii (Htg.), overwinters in a cocoon in the ground and has an adult emergence period that may last two months. Ecological studies of this insect require information on the number of adults emerging and the seasonal pattern of emergence. Several types of open-bottomed screen emergence cages without traps were tested but the insects caught in such cages were difficult to remove. Also, many of the adults were lost in the vegetation unless the cages were visited more frequently than was practicable. The trap described here, attached to a screen cage, eliminates the objections given above and could be of use to persons interested in insects which emerge from the soil.

Two non-destructive sexing techniques suitable for use in the field and laboratory are described, and tested with the Warren root collar weevil, Hylobius warreni Wood (Coleoptera: Curculionidae). On the second visible abdominal sternite of males is a longitudinal depression that is absent on females. In addition, setae on the last visible abdominal sternite of females are arranged longitudinally; setae on males are arranged radially. For the first character, accuracy was 90% and sex could be determined without the aid of magnification. The latter character was slightly more reliable, at 95% accuracy, but required at least 12× magnification.

The orientation of mature, female Frontinella communis (Hentz.) on horizontal sheet webs was recorded in the field. Spiders fully exposed to direct solar radiation oriented independently of the sun at ambient air temperatures from 18 to 27 °C., but at higher temperatures, corresponding to web temperatures from 30 to 37 °C., they oriented toward the sun's disk in both the horizontal and vertical planes. The orientation of spiders in shade was independent of the sun's azimuth over the entire range of air temperatures experienced (18 to 34 °C). During light to moderate rainfall spiders oriented in the direction of the prevailing wind and the vertical displacement of the body axis from the typically horizontal position varied directly with rainfall intensity.

During the course of a study of the bionomics of the pitted ambrosia beetle, Corthylus punctatissimus Zimm., in southern Ontario in 1959, the method of overwintering fungal spores and their transmission from brood galleries to healthy plants by the beetles was determined. This process was not clearly understood with respect to any of the ambrosia beetles until recently when Francke-Grosmann (1956) described in detail the different structures, present in several species of Platypodidae and Scolytidae, used in storing fungal spores. In Scolytidae she found that the females of some Trypodendron species store spores in tube-like structures within the prothorax (invaginations of the prothoracic wall); that females of Xylosandrus germanus Bldf. and Anisandrus dispar Fabr. keep spores overwinter in shallow pouches in the intersegmental membrane between the pronotum and mesonotum; that females of Xyleborinus saxeseni Ratz. store them in a small cavity at the anterior edge of the elytra; and that females of Xyleborus pfeili Ratz. store the spores in a receptacle on the “posterior” abdominal tergite. In some species of Platypodidae she found somewhat similar structures in both males and females. In 1959 Fernando (1959) described spore storage by the shot-hole borer, Xyleborus fornicatus Eichh. He found that females store spores in sacs on either side of the head, situated anterior to the brain, and that the sacs open by ducts into the upper part of the oral cavity.

Aerial photographs of corn fields in southwestern Ontario were photographically enhanced and subsequently computer-analyzed to determine levels of corn aphid infestation. The flight line included 87 fields, 42 of which were infested to varying degrees. The levels of infestation varied from 35.6% to 67.1% determined from five representative fields.

Field-collected Agonum muelleri (Herbst) adults were videotaped to assess their ability to climb soybean (Glycine max (L.) Merr. (Fabaceae)) plants. All individuals climbed up and down soybean plants multiple times. Agonum muelleri spent from 12.5 ± 3.4% to 54.1 ± 11.3% of their time on soybean plants. Caged A. muelleri adults on plants infested with soybean aphids, Aphis glycines Matsumura (Hemiptera: Aphididae), reduced the number of apterous adults. The presence of predators had an indirect effect on the density of nymphal aphids by reducing the numbers of adult aphids. Agonum muelleri, an abundant carabid in soybean fields, readily climbs soybean plants to feed on soybean aphids.

Aphids of the genus Cinara are capable of causing serious growth reduction of Douglas-fir seedlings. Growth of infested seedlings may be only one-fourth to one-half that of uninfested seedlings. The aphids are easily controlled by injecting demeton around the base of the seedling. The presence of ants to clean up excessive honeydew is shown to be beneficial for the aphids.

Residual and contact toxicities of several insecticides to larvae and adults of insecticide-susceptible (four insecticides) and insecticide-resistant (three insecticides) Colorado potato beetle, Leptinotarsa decemlineata (Say), were measured in laboratory studies. For both methods of exposure, azinphosmethyl was the least toxic to all life stages tested. The residual toxicity of deltamethrin was at least 4.4-fold higher than either cypermethrin or endosulfan. With the insecticide-susceptible strain, residual toxicities of azinphosmethyl, endosulfan, and deltamethrin were, respectively, 3.5, 5.9, and 4.1 times higher to first instars than to adults and 1.2, 8.1, and 1.6 times higher to third instars than to adults. Contact toxicities of azinphosmethyl, endosulfan, and deltamethrin were, respectively, 3.3, 2.9, and 1.4 times higher to insecticide-susceptible third instars than to adults. In most comparisons, susceptibilities of fourth and third instars were similar. With the insecticide-resistant strain, azinphosmethyl, endosulfan, and deltamethrin were, respectively, 3.2, 1.6, and 8.0 times more toxic to third instars than to adults. The importance of differential life stage toxicity to current control recommendations for Colorado potato beetle is discussed.

Reticulitermes flavipes (Kollar) is best known throughout southwestern counties of Ontario, Canada, as an urban pest. Little is known, however, of the presence of this termite in nonurban settings in Ontario. In this study, we confirmed the existence of a population of R. flavipes on the shores of Lake Erie within Point Pelee National Park. A systematic trap survey conducted along the park's semi-vegetated west beach revealed several zones of termite activity. An analysis of trap response at one location indicated an association between termite activity and smaller sized, moderately decayed woody debris. Further, microsatellite DNA analysis suggested the presence of at least three genetically distinct colonies, each likely headed by multiple inbred reproductives. Together these data suggest that termite activity is linked to food quality, and that single colonies are potentially long-lived through multiple generations of inbreeding. Assuming it is derived from a population reported from Point Pelee in 1929, the study population is the oldest known eastern subterranean termite population in Ontario.

In southern Alberta there are several species of aphids that produce galls on poplar trees (Harper, 1959). These aphids are all in the subfamily Eriosomatinae and in the genera Pemphigus Hartig, Thecabius Koch, and Mordwilkoja Del. G. Two of the species are of economic importance, Pemphigus betae Doane, a pest of sugar beets in Alberta and parts of United States (Harper, 1957; Maxson, 1916; Parker, 1915), and Pemphigus populitransversus Riley, a serious pest of crucifers in Texas (Wene and White, 1953). Both species overwinter on poplar as eggs. In spring the fundatrix emerges from the egg and feeds on the poplar leaf, initiating a gall in which the winged fundatrigeniae are produced. During the summer the fundatrigeniae migrate to the secondary host where they produce the wingless alienicolae; in the fall these in turn produce the winged sexuparae, which migrate to the poplars where they produce the wingless sexuales. The female sexuales, after mating, deposit eggs on the poplars to complete the life cycle (Harper, 1957; Jones and Gillette, 1918; Parker, 1914).

In two laboratory experiments, adult western conifer seed bugs, Leptoglossus occidentalis Heidemann, did not feed on seed infested by the Douglas-fir seed chalcid, Megastigmus spermotrophus Wachtl. When presented with seed lots containing 0, 20, 40, 60, 80, or 100% chalcid-infested seed, seed bugs fed on uninfested seed only when the percent chalcid infestation was ≤ 40% (Exp. 1), ≤ 20% (Exp. 2, females), or ≤ 60% (Exp. 2, males). In a third experiment, nymphs exposed to similar seed lots did not feed on M. spermotrophus when sound seeds were present. However, when exposed to 100% chalcid-infested seed, nymphs in two of 10 replicates fed on M. spermotrophus. Feeding by seed bugs caused seeds to lose 51% of their weight on average, but 18% of 43 test seeds on which seed bugs had fed germinated. In three Douglas-fir orchards surveyed, both species exhibited a clonal preference, but the ranking of clones preferred by each species was not the same. These results suggest that the impacts of L. occidentalis and M. spermotrophus are segregated and additive.

Antifeedants for controlling larval feeding of several Neodiprion sawflies were evaluated in laboratory and field studies. Nine commercially available insect antifeedants and a hexane extract of the juvenile foliage of jack pine, Pinus banksiana Lambert, were tested on larvae of six species. In laboratory bioassays larvae exhibited varying sensitivity to antifeedants; generally species with monophagous or restricted oligophagous feeding habits were most sensitive. In the laboratory the Swaine jack pine sawfly, Neodiprion swainei Middleton, had severely restricted feeding, development, survival, and fecundity. Triphenyltin hydroxide was toxic to N. swainei and to European pine sawfly, N. sertifer (Geoffroy). In field tests certain antifeedants disrupted N. swainei feeding and development. The colonial behavior of larvae often was disrupted and solitary larvae fell from trees or wandered on twigs. Colony disruption by most antifeedants was temporary and many larvae resumed feeding.

This paper contains notes affecting the classification of the Bruchidae of United States and Canada, a list of all species found north of Mexico, and a list of World genera and their type-species. The Mexican Merobruchus vacillator (Sharp) is added to the fauna of this area. Transferred from our list to that of Latin America are: Acanthoscelides californicus (Boheman), Megacerus eugenie new name for Bruchus ramicornis Boheman nee Erichson, and Mimosestes innotatus (Pic.). The following are synonymized: Spermophagus (Zabrotes) semicinctus Horn (1894) with Zabrotes subfasciatus (Boheman 1833); Bruchus subserripes Fall (1910) with Acanthoscelides compressicornis (Schaeffer 1907); Lithraeus electus Bridwell (1952) with Lithraeus elegans (Blanchard 1851); Bruchus alboguttatus Motschoulsky (1874) with Meibomeus musculus (Say 1831); Bruchus bivulneratus Horn (1873) with Bruchus abbreviatus, inadvertently validated by Say = Sennius abbreviatus (Say 1824); Bruchus nigrinus Horn (1873), B. nictitans Motschoulsky (1874), and B. depressus Fall (1912) with Sennius cruentatus (Horn 1873); Bruchus pythonicus Pic (1913) with Stator pygidialis (Schaeffer 1907); and Bruchus biguttatus Fabricius (1801) = Bruchus biguttellus Schoenherr (1833) with Callosobruchus chinensis (Linnaeus 1758). Original spellings of the specific names of two species are revived: Megacerus pygidalis (Motschoulsky) nee pygidialis Pic, and Megacerus discoidus (Say) nec discoideus: authors. Bruchus lividus J. E. LeConte 1824 is placed in our list as an unrecognized species. Thirty-five new combinations are proposed.

A descriptive key based on phenotypic characteristics displayed by cocoons and/or pupae is offered as a tool for identification of primary parasitoids of the armyworm, Pseudaletia unipuncta (Haworth), in eastern Ontario. A second key based on structural differences of the last-instar larval mouthparts and tracheae is offered as a means to differentiate secondary parasitoids associated with the above-mentioned primary forms. Photographs of the cocoons, illustrations of the last-instar larval mouthparts and tracheae, and biological notes on pre-imago habits are included as supplemental criteria for species identification.

Aside from M. acerbus (Jordan), which is apparently a breeding parasite of Tamias striatus (L.), a chipmunk, the holarctic genus Megabothris Jordan 1933 appears to be truly associated with the Microtinae, some of the species showing special affinities for particular species of these mice, others infesting several species, or even genera, within a geographical region.

The nearctic Megabothris asio (Baker) favours the common meadow vole, Microtus pennsylvanicus (Ord), and occurs throughout most of the range of that mouse. The writer recognizes two valid subspecies, M. asio asio, which is restricted to eastern North America, and M. asio megacolpus (Jordan), of western North America. The nominate race ranges from Labrador to Delaware. M. asio megacolpus (=M. asio orectus Jord.) ranges from western Quebec, western Ontario, and Michigan westward to the Coast Range, and from California north at least to the 60th parallel.

The invasive woodwasp Sirex noctilio Fabricius (Hymenoptera: Siricidae) is obligately associated with the symbiotic white rot fungus Amylostereum areolatum (Chaillet ex Fries) Boidin (Basidiomycota: Amylosteraceae), and shows positive chemotaxis to volatiles emitted by this symbiont. After introduction to North America, S. noctilio was collected carrying another fungus species Amylostereum chailletii (Persoon) Boidin, used symbiotically by native North American Sirex Linnaeus. We conducted flight behaviour studies in a walk-in flight tunnel to evaluate specificity of the attraction of mated and unmated S. noctilio to its primary symbiont, A. areolatum, versus the alternative symbiont, A. chailletii. Fewer unmated than mated S. noctilio females responded to either of the fungi. Unmated females showed no landing preference but mated S. noctilio females were attracted to A. areolatum although avoidance of A. chailletii was not complete. Chemical analysis demonstrated major differences in the volatile profiles of the two fungal species. Sesquiterpenes dominated the A. areolatum samples, whereas only two aromatic volatiles were consistently present in the native A. chailletii.