European corn borer moths were caught in an ultraviolet light trap from early June to late October at Harrow, Ont. Two conspicuous peaks of light trap catches occurred each year, corresponding to two generations, but a third generation was deduced from three peaks of occurrence of virgin females. The number of moths which could be caught with nets in the day time correlated with the light trap catch of the previous night (r = 0.7). Most of the moths caught in the light trap or in nets were females but males predominated in the early June, September, and October catches. The shortage of males in the second generation was shown to influence the proportion of females mating, but not the number of spermatophores per female. Most females mated once and the number of matings per female did not differ enough between years to account for differences in adult populations.

Seasonal distributions of adult emergence and larval drop for Anoplonyx luteipes (Cresson), A. canadensis Harrington, and Pristiphora erichsonii (Hartig) are compared. Larval populations of A. luteipes have a significant positive correlation with those of P. erichsonii, while A. canadensis adult populations show a significant negative correlation with P. erichsonii larval populations.

During 1971 a study was conducted to determine the amount of the various Douglasfir cone structures (bracts, scales, and seeds) consumed by the Douglas-fir cone moth, Barbara colfaxiana (Kft.), in the Buckhead Seed Production Area, Willamette National Forest, Oregon. It was not the intent of this study to develop a complete energy budget for B. colfaxiana, but rather to determine the number of calories consumed, on the average, by an individual during the larval stage. The behavior of the various larval instars has been discussed by Radcliffe (1952), Keen (1958), Hedlin (1960), and Nebeker (1977). The calorie was selected as the unit of measure due to its usefulness in modeling energy transfer from one component to another in the forest ecosystem.

The South American species of Oplachantha Rondani are reviewed and a key to them presented. New species are atricalx, Peru; pallida, Colombia; albihirta, Colombia; fuscipes, Venezuela; divisa, Ecuador; and atriceps, Peru. New synonymies are (iubata Enderlein) = pulchella (Williston) and (tristis Enderlein) = cincticornis Enderlein. Allognosta Barbiellinii Bezzi, Hoplacantha nigerrima Lindner, and Antissops Bezzii Lindner, sometimes referred to this genus or to Berismyia, belong to an as yet undetermined genus.

Keys, descriptions, and illustrations are presented for the identification of the larvae, pupae, and adults of the four species of black flies known from Iceland, viz. Prosimulium (Prosimulium) ursinum, Simulium (Psilozia) vittatum, S. (Eusimulium) aureum, and S. (E.) vernum. Maps depicting their distributions within that country, and brief biological notes are given.

In mid-September 1974, adults of Ichneumon canadensis Cress, emerged in the laboratory from pupae from the soil under field cages at Grosse Isle, about 15 miles northwest of Winnipeg, Man. The field cages had been stocked with laboratory-reared fifth-instar larvae of M. configurata. The cages were removed after 12–15 days when the larvae had finished feeding. Eleven I. canadensis emerged from 1671 pupae collected from experiments set up on 29 July, 2 August, and 12 August; none emerged from 229 pupae collected from experiments set up on 17 and 22 July. Parasitization could have been by adults that either were trapped inside the cages when they were erected, or that emerged later from the soil inside the cages, or that discovered the host-containing area after the cages were removed but before the soil was sifted. As this was the first report of this ichneumonid parasitizing M. configurata, various aspects of the parasite's biology were investigated.

A review of existing records of Tabanidae collected in Labrador and Newfoundland compiled by Philip (1962) reported the total number of species verified from Newfoundland to be 14 in four genera, and for Labrador, 21 species in five genera.

Mortality of hibernating codling moth larvae from the Georgian Bay area and the Niagara peninsula of southern Ontario was not affected after exposure to temperatures as low as −16.7°C for 48 h. One hundred per cent mortality occurred at −20.0°C after pre-conditioning the larvae for several weeks by exposure to gradually decreasing temperatures. In neither area were the minimum winter temperatures low enough nor of sufficient duration to significantly affect larval mortality. There was no effect on pupal or adult survival or on the fecundity and fertility of surviving adults following exposure of larvae to low temperatures.

Tetrastichus julis (Walker), a European larval endoparasite of the cereal leaf beetle, Oulema melanopus (L), has become widely established in southern Ontario. In 1975, rates of parasitism in 14 counties varied from 15% in the east to 95% in the west Dispersal into Ontario was natural and is attributed to extensive colonization of the parasitoid in Michigan and other parts of the U.S. midwest. Reasons for its success in Ontario are suggested.

The development of insects that live within plant tissues has always been difficult to observe. Reliable information on their biology has been obtained by making daily dissections of infested plants but that procedure sacrifices both insects and plants and does not allow continuous observations of individual insects from plant entrance to emergence. Milner et al. (1950) developed an X-ray technique which provided satisfactory delineation of internal infestation of insects in grain. With their method they were able to observe insect development of the granary weevil, Sitophilus granarius (L.), and the rice weevil, Sitophilus oryzae (L.), without any deleterious effects of radiation upon their development. Other techniques applied in seed testing (Metzner 1962), coffee beans, and nut evaluations (Esteves 1959; Vilar 1966) are not applicable to soft vegetable materials such as maize stalk and ear.

Camponotus pennsylvanicus (De Geer) workers concentrate their foraging efforts in the vicinity of a new food source. Experiments with artificial “trees” confirm that these ants lay chemical trails when they locate food and under other circumstances. Marks left by ants travelling over smoked paper indicate that the trail consists of a series of streaks, sometimes variable in length, and that ants following trails make regular alternate deviations. Trails are laid extensively in the immediate vicinity of food. A trail is not reinforced by all gorged workers passing over it.

The trails activate other workers and provide a means of orientation but are clearly non-directional. A bioassay with various organs indicated that the hind gut is the source of the trail substance.

When a strong direct light is available, attention to trails dwindles and ants eventually use light orientation to reach the food, often following more direct routes at that time. Physical contact between workers may activate them but provides no directional information and may lead to temporary disorientation.

It is often necessary in queen quality, package bee development, and wintering studies to locate the queen at different times to determine her presence, weight, location, etc. In the spring, colonies are small and locating the queen is not difficult. However, in late summer, when colonies reach up to 60,000 worker bees in five or six supers, the task becomes very difficult and time consuming. While the use of radioactive tags as a means of following the movement of insects has been well established (Amason et al. 1950: Green et al. 1957; Gomez et al. 1962; Baldwin and Cowper 1969), their use for studying the movement of bees has been limited. Radioactive paint was used by G. A. Tomes (1940) and Raudszuz (1958) for marking queens but apparently proved unsuitable. This study was conducted to determine the possibility of using platinum-iridium (IR-192) tags as a means for rapid, repeated recovery of queens during the producing season

Special techniques are necessary to study the morphology of complex chitinous structures such as insect mouthparts. Many of the details are beyond the resolution of light microscopy, and the methods of conventional electron microscopy do not include the efficient production of serial sections for reconstruction. Although the scanning electron microscope (SEM) permits detailed observation of 3-dimensional surfaces, it cannot see internal surfaces and under complex folds, nor can it readily show the thickness of solid structures. To study the details of the stylet tips of the bug Rhodnius prolixus (Stål) several techniques were tried. Initially, specimens had been embedded in paraffin wax, sectioned, dewaxed, and prepared for the scanning electron microscope. Because of difficulties in sectioning the hard stylets and poor preservation of fine structure, this method was abandoned in favour of one using thick sections (2 μm) of material embedded in a mixture of Epon and Araldite.

In the study of insect parasites of the darksided cutworm, Euxoa messoria (Harris), fourth- to seventh-instar larvae were collected from a field at Delhi, Ont., and reared in the laboratory. A total of 701 insect parasites including six species of Hymenoptera and four of Diptera, were reared from the 3970 darksided cutworm larvae collected in 1973 and 1974.

Thirteen species of insect parasites of E. messoria are listed. Ten of these species were reared in the present study from E. messoria in Ontario and all of them are primary and internal parasites. Of the 10, only two have previously been reported as parasites of E. messoria. Host–parasite relationship and the degree of parasitism are given for the 10 species reared in Ontario.

The bertha armyworm, Mamestra configurata Wlk., is a periodic pest of rape in western Canada. After a massive outbreak of the species during 1971 and 1972, investigations on the insect were intensified in many laboratories. A technique for rearing the larvae on a semi-defined diet was developed by our Winnipeg-based group and has been used successfully to rear 21 consecutive generations of M. configurata in the laboratory (Bucher and Bracken 1976). Our current culture originated from a few pupae field-collected in Alberta and has been carried through 21 generations without addition of new stock.

The microsporidian spores infecting some Canadian populations of Tyria jacobaeae have been characterized for the first time at the ultrastructural level. Differences exist between this microsporidian and others described at the same level elsewhere.

We analyzed a roll of 16 mm motion-picture film of the swarming of a cecidomyiid midge, Anarete pritchardi Kim, to calculate the acceleration of individual insects. We find that the midge moves with high accelerations, occasionally twice the acceleration of gravity, and that the midge is also subject to an inward force predominantly at the swarm edge. Energetics of midge flight is also considered by using accelerations and related data.

Attractants were found for males of 12 moth species: Acronicta grisea Walker, Andropolia contacta Walker, Argyrotaenia dorsalana Dyar, Chrysaspidia putnami (Grote), Chrysaspidia venusta Walker, Eurythmia hospitella Zeller, Exartema appendiceum Zeller, Mutuuraia mysippusalis (Walker), Decodes horarianus Walsingham, Polia atlantica Grote, Sitochroa chortalis Grote, and Pandemis canadana Kearfott. For five of these species single pure compounds were useful attractants, while the remaining seven required binary mixtures whose components when tested singly showed little or no attractancy.