Twelve series of collections of adults from emergence traps in four streams and from six different years provide data on the annual emergence patterns of Plecoptera. Of the 24 species collected, 15 were in sufficient number to be studied in detail. Each species has a typical emergence pattern which it maintains year after year despite climatic variations. Two types of pattern are distinguished: a synchronous and an extended emergence. Species with a wide temperature tolerance can, however, present both types. Usually equal numbers of both sexes are collected and the males on the whole often emerge before the females. Closely related species normally have different emergence periods.

Laboratory experiments at various constant temperatures indicate a theoretical threshold of about 40°F. for spinning of cocoons by eonymphal larvae of Neodiprion swainei Midd. As temperatures fall below 52.5°F. the increase in mortality and time required to spin is pronounced. The optimum temperature is estimated to be around 60°F. Field investigations for three consecutive years show a close correlation between rate of spinning and temperature. Temperature is considered as a prime factor influencing the spinning of cocoons and is possibly one of the more important factors governing the population dynamics of N. swainei in the Province of Quebec.

Neem, Azadirachta indica A. Juss. (Meliaceae), seed oil (NSO) added to meridic diet at concentrations as low as 0.016% reduced pupation and prevented adult eclosion of obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae). At a rate of 0.0016%, NSO reduced the fitness of C. rosaceana, resulting in longer developmental times, lower adult eclosion rates, and reduced egg production compared with controls. The neem insecticide Margosan-O TM produced comparable results based on concentrations of the most biologically active constituent, azadirachtin. Pupation was completely inhibited at concentrations of 0.25% and 1.0% for larvae exposed at 5th or 6th instar, respectively; rates as low as 0.016% reduced pupal weights and adult eclosion rates. For larvae transferred to treated diet at 5th instar, physical abnormalities in the wings of adults occurred at a rate of 0.004% NSO and increased with increasing treatment rates. NSO at concentrations as high as 2.0% was not antifeedant to neonate larvae, based on 24 and 48 h choice test bioassays, when incorporated into a meridic diet.

Can. Ent. 98: 789-791 (1966) The life-span of Swaine jack-~ine sawfly adults was studied under various constant and alternating temperatures and at four different values of relative humidity. Temperature significantly influenced the life-span of both sexes according to a non-linear equation, and relative humidity according to a linear regression. The influence of temperature varied with relative humidity in the case of males but not in the case of females. The life-span of both sexes was sh,orter at alternating temperatures than at constant temperatures. AbstractCan. Ent. 98: 794-798 (1966) The temporat pattern of emergence of Anax junius Drury was studied by making standardized exuvial collections in a farm pond near Montreal. Supports available to emerging larvae were restricted artificially in order to standardize the collecting area. Emergence lasted for 30 days (29 July to 27 August 1965), the peak lying between days 10 and 15; A . junius thus behaved as a "summer species" (sensu Corbet 1954). The emerging population comprised about 48% males.N o adults were seen flying over the pond except during the maiden flight.

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