The sunflower maggot is native to North America. It has been recorded from Maine and New Brunswick through Quebec to Alberta and California and as far south as New Mexico and Florida. It was collected by Criddle at Aweme, near Treesbank, Manitoba, in 1905 and is known to have been present in cultivated sunflowers in southern Manitoba since 1944. Heavy infestations have occurred since 1948.

Parker et al. (1955) reported the spectacular outbreaks and migrations of the migratory grasshopper, Melanoplus bilituratus (Wlk.) in 1938 and 1939 in the north-central states of South Dakota, North Dakota and Montana, U.S.A. They recorded the extension of the flights northward into the Canadian provinces of Manitoba Saskatchewan and Alberta, and mentioned that the progeny of the migrants invading southern Saskatchewan in 1939 moved further north in 1940.

In a preliminary report (Robinson, 1959) it was shown that the plant growth regulator maleic hydrazide (MH) caused both nymphal mortality and reduced fecundity to the pea aphid, Acyrthosiphon pisum (Harris), caged on treated broad bean, Vicia faba L. It was also stated that 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), and 2-methyl-4-chlorophenoxyacetic acid (MCPA), applied by root absorption to broad bean had no effect on adult or nymphal mortality, or fecundity of adult A. pisum, at the rates used.

The larch sawfly is a common defoliator of trees of the genus Larix throughout the Holarctic Region. In North America it has been reported from every province of Canada but in the United States it is confined to the northeastern States, the Lake States, and north-western Montana (Drooz, 1956). The northern limits of distribution have not been determined, but extend as far as 61° N. lat. north of Saskatchewan.

Many experiments in entomology are evaluated by counts of the number of individuals in each unit of space or time. The original counts may be summarized in a frequency distribution showing the number of units containing 0, 1, 2, 3 … individuals of a given species. If a population is distributed over a number of units at random, the distribution of numbers per unit will approximate a Poisson series, the variance of the population being equal to its mean. Such distributions are rare in nature. Usually there is an excess of unoccupied units and of densely occupied units over Poisson expectation. This departure from randomness is attributable to contagion, where the presence of one insect in a unit increases the probability of others occurring in that unit. It results from the egg-laying habits of adult insects, gregariousness of feeding larvae, etc.

Studies in the Entomology Division at Ottawa in 1957 and 1958 led to the design and building of a “walk-in” air-conditioned cabinet for rearing insects, air motion and distribution as well as temperature and humidity being precisely controlled. The air is heated, cooled, humidified, and dehumidified in four separate ducts. A quadrate funnel for the air exhaust gives especially even distribution of the air within the cabinet, the air moving at 25 to 30 f.p.m. Temperature and humidity can be held at any desired levels from 65 to 85 ± 0.5°F. and from 45 to an accuracy of ± 1 per cent R.H. provided that ambient conditions are within 65 to 85°F. and 5 to 85 per cent R.H. This paper describes the cabinet and air-conditioning system and the main principles on which the apparatus is based.

Knowledge of the insects affecting livestock in Eastern Canada, except possibly cattle grubs, has been inadequate. The distribution and control of cattle grubs in Eastern Canada were studied by Cameron (1918), Stevenson (1934), and Gibson and Twinn (1936). Baker et al. (1950, 1955) reported the progress made in reducing cattle grub populations in the warbly fly control campaign begun in 1948 in Ontario. Occasional records of livestock pests have appeared in The Canadian Insect Pest Review and the annual reports of the Ontario Department of Agriculture. Hadwen (1923) and Hearle (1938) discussed the various pests injurious to livestock in Canada, but did not refer specifically to Ontario.

The emphasis in mosquito identification has been centered for the most part on the fourth-instar, or mature, larval stage and on both sexes of the adult forms. Some stress in recent years has been placed on pupal and egg morphology; however, as pointed out by Bohart (1954) and others, in comparison with the vast amount of literature on these stages, the amount of work published on the identification of early-instar mosquito larvae has been relatively slight. Regardless of the reasons for this, it would be, for instance, of immeasurable value to a person studying mosquito ecology to be able to identify directly to species any larval stage of the mosquito that he might collect. It is hoped that this paper, even though limited to Minnesota Aedes, will contribute further to the ability to recognize first-instar Aedes larvae and that it will serve as an added stimulus to workers in other geographical areas to collect and assimilate materials in a similar manner.