Laboratory and field experiments were designed to determine the effect of insect predators on the immature broods of Dendroctonus brevicomis LeConte. The results indicate that predation is dependent on the predator density and the time predator and prey are exposed together. Prey density was generally very high and had little effect on the rate of predation. The corroboration of laboratory and field experiments give confidence to the conclusion that the constant predation rate (0.261 prey per predator per day) can be used to estimate western pine beetle mortality from predation, provided temperatures remain within the 60° to 70°F range.

The Canadian and Greenlandic species of Pterocomma Buckton are described and illustrated and a key provided. This includes all but one of the known North American species as follows: bicolor (Oestlund); populifoliae (Fitch); populeum (Kaltenbach); salicis (Linnaeus); sanguiceps new species; smithiae (Monell). The phyletic position of the Pterocommatini is discussed. It is apparent that the Pterocommatini is not a primitive group of aphids.

Populations of the mayfly Heptagenia hebe McDunnough in areas of New Brunswick air-sprayed with DDT for budworm control for eight successive years, when tested as nymphs taken from the streams, showed LC50 levels 3 times as high as those in untreated areas. Populations surviving an airspray in 1965 proved to be 12 to 40 times as DDT-resistant as the normal. Pre-spray populations of Stenonema fuscum (Clemens) showed a 5-fold resistance, and post-spray populations of Stenonema interpunctatum (Say) showed a 10-fold DDT resistance when those from treated areas were compared with those from untreated. The DDT-resistant nymphs of H. hebe detoxified DDT to DDE 15 times faster than the normal nymphs; DDE was also the metabolite in S. interpunctatum. In both these species the DDT-resistant nymphs absorbed roughly twice as much DDT as the normal.

The adults, mummies, and final-instar larvae of the eight hymenopterous parasites of the pea aphid, Acyrthosiphon pisum (Harris), in Eastern Canada are described and illustrated. The history, synonymy, and biology of each species, and the problems of species differentiation in two of the genera, Aphidius and Praon, are discussed. Keys are given to separate the adults, mummies, and cast skins of the last larval instar.

In feeding tests with 20 different dry foodstuffs, some, usually those of high carbohydrate content, permitted Tribolium confusum jacquelin du Val to survive and develop reasonably well. Differences between the sugar content of Sugar Pops and Corn Flakes were probably the reason for better growth on the former than on the latter. Moreover, raisins and bran, i.e. Raisin Bran, was a better food than Bran Flakes. The hygroscopic properties of dehydrated peaches and of pineapple juice soon rendered them unfit as food for T. confusum. It is apparent that though some modern dry foodstuffs that lend themselves well as stored products may be highly susceptible to insect attack, others seem to be “self-protected” from serious insect infestation. This suggests that stored food products might be packaged and handled selectively according to their susceptibility rating and so result in obvious economies in their handling.

A technique for rearing the root weevil, Hylobius warreni Wood, is described and figured. Plastic cages containing weevils were attached to stumps placed in pans containing moist moss. Observations of adult behaviour and records of eggs deposited, egg mortality, and early larval development are presented as evidence of success of the technique. Third instar larvae were obtained without handling and required only the addition of moisture.

Macrosiphum parvifolii is described from British Columbia. It is a heavily pulverulent, almost flocculose species that is known only from red huckleberry, Vaccinium parvifolium Sm.

The escutcheon or badge of the Lyman Entomological Museum (see Can. Ent. 96(12) cover and page 1485) bears a likeness of Haploa confusa (Lyman 1887), which was originally described in the genus Callimorpha. The species was described from four syntypic specimens in Lyman's collection, all from Montreal. Four additional specimens in “the Cambridge Museum” (Museum of Comparative Zoology, Harvard University, Cambridge, Mass., U.S.A.) are also syntypes as they were mentioned by Lyman following the original description. To date, no lecrotype has been selected for this species.

The subfamily Acicnemidinae is for the first time recorded in America, descriptive details and illustrations are given for its introduced representative, the European Trachodes hispidus (Linnaeus), notes on the distribution and synonymy of Acicnemidinae and Trachodes are presented, and the subfamily keys of Blatchley and Leng and of Kissinger are emended to include the Acicnemidinae.

The species described as Pachynematus gregarius Marlatt is removed from the genus Micronematus and placed in the genus Eitelius. A key to the males and females of the two known species of Eitelius, and illustrations, are provided.

Chrysothyridia n. gen., related to Didymostoma Warren, is described, with Gonocausta invertalis Snellen as type-species. C. triangulifera n. sp., from the Philippines, type locality Mt. Makiling, Luzon, is described. Didymostoma is recognized as distinct from Bocchoris Moore and Bocchoris aurotinctalis Hampson is transferred to Didymostoma.

The life history and habits of Epinotia solandriana Linnaeus are discussed and the immature stages described. Information is given on distribution, host trees, variations in wing pattern of the adults, laboratory rearing, and parasites.

Eggs, larvae, and cocoons of Neodiprion nanulus nanulus Schedl, from an isolated infestation in a small plantation of red pine, Pinus resinosa Aiton, near Fredericton, N.B., were reared for parasites. Nine species of ichneumonids were obtained, eight of which are first records from this host in the Maritime Provinces.

The apholate-sterilized males of Aedes aegypti deplete their sperm earlier than the normal males. This indicates reduced fecundity of the sterilized mosquitoes and may result from either death of gonial cells at different stages of development or an inhibited rate of spermatogenesis.