Prionomitus mitratus (Dalm.), Trechnites insidiosus (Crawford), Pachyneuron sp. and Asaphes probably vulgaris Walker are recorded as parasitic in Psylla pyricola L. The first two are primary parasites, the latter two are hyperparasites. All are new records for British Columbia. The biologies of T. insidiosus and Pachyneuron sp. are discussed briefly.

Can. Ent. 102: 1390Ent. 102: -1394Ent. 102: (1970 Canzpylomma verbasci (Meyer) overwinters as an egg on apple, pear, Rosa spp., and Amelanchier sp. On pear, the chief prey are eggs and nymphs of Psylla pyricola Fijrster and all stages of Panonychus ulmi (Koch). C. verbasci is partially phytophagous but prolonged feeding by nymphs on pear fruits caused no injury. During the summer, C. verbasci lives and reproduces as a predatorphytophage on a number of herbaceous plants. Three, possibly four, generations occur in the southern interior of British Columbia. The effects on C. verbasci populations of a number of pesticides applied to pear trees are reported.

The optimum temperature for rate of development and survival of immature stages of Coccinella novemnotata Herbst was found to lie between 70° and 80°F. Different photoperiods between 10 and 18 hours per day did not influence rate of development or survival. With a 16-hour photoperiod the mean number of eggs laid per female and mean longevity of females were greater at 70° than at 80°F, but not significantly so. At 90°F egg production was sharply curtailed and most eggs produced were infertile, probably due to inactivation of sperm in the male. Photoperiods of 10, 12, and 18 hours per day induced diapause in a large percentage of adult females; intermediate photoperiods of 14 and 16 hours per day were much less effective. Low temperature and lesser amounts of food available to adult females increased the effectiveness of the short and the long photoperiods for inducing diapause. The stage susceptible to induction of diapause, or conversely the initiation of gonad maturation, was determined to be the young adult from emergence to 7 days of age. The results of experimental data are related to a field study of the biology of this insect in California.

No abstract

Can. Ent. 109: 165-169 (1977) At constant temperatures between 10.0" and 32.2"C with 16 h photoperiod development of eggs and nymphs was slowest at 10.0" (61.8 days av.) and most rapid at 26.7OC (27.0 days av.). Mortality of eggs and nymphs was moderate (43.78) at 10.OO, least (24.2%) at 21.1°, and 100% at 32.2"C. Between 15.6" and 35.0°C, 16 h photoperiod, fecundity of winter form adults was greatest (486.3 eggs av.) at 15.6" and lowest (0.0 eggs) at 35.0QC. For summer form adults fecundity was moderate (212.4 eggs av.) at 15.6", maximum (444.9 and 447.3 eggs av., respectively) at 21. l o and 26.7"C, and least (2.8 eggs av.) at 35.0°C. Longevity of male and female winter and summer forms was greatest at the low temperature and least at the high temperature. These data are discussed with relation to field observations of natural pear psylla populations and control programs.