Four major categories of neurosecretory cells (A, B, C, D) were distinguished in the brain of Triphaena pronuba L. by staining sections with paraldehyde fuchsin and counterstains. These comprised nine types of cells, seven of which were recognizable for analysis of their secretory products. Histochemical tests indicate that the lepidopteron brain has a multiplicity of neurosecretory cells, each type producing chemically different secretions.

Duplicate benthic stream samples were collected from three sites on Sandy Creek (Lake Ontario Watershed) in Western New York, 8 and 22 September, 1970. Samples taken on 8 September were preserved in 10% formalin. Samples taken on 22 September were not preserved. Insect specimens were removed from both sets of samples by flotation with a sucrose solution of 1.12 sp. gr. Preserved and unpreserved samples were compared for efficiency of recovery of insect larvae. Mean recovery for preserved samples was 90.78% compared with 83.03% for unpreserved samples. The range of recovery values for unpreserved samples (66.7%) was more than twice as great as that of preserved samples (29.5%). A paired t-test for means of all taxa showed no significant difference (P < 0.001) between recovery values for preserved and unpreserved samples. In fact, preservation may enhance the recovery of certain groups—Zygoptera, Hemiptera, Trichoptera, and Chironomidae. Apparently samples may be preserved without sacrificing recovery of any specific groups of insect larvae.

Two hymenopterous parasites Bathyplectes curculionis (Thomson) and Tetrastichus incertus (Ratzeburg) parasitized 16.5% of their principal host the alfalfa weevil Hypera postica (Gyllenhal) in 1970. A total of 2703 parasites was reared and released in localities where their activity was reported low or non-existent prior to this study. Maximum parasitism by T. incertus and B. curculionis occurred later than periods of peak weevil larvae activity; however, T. incertus emerged earlier in several areas possibly as a natural adjustment of its life cycle, and B. curculionis persisted in multiple non-diapausing generations until late fall. The braconid parasite Microtonus aethiops (Nees) shows promise in becoming a very effective control agent through its ability to prevent weevil oviposition now that it is rapidly dispersing throughout New York. Having parasites established statewide through both releases and natural dispersal has lowered weevil populations below critical levels, and will increase parasite effectiveness in dealing with future alfalfa weevil generations.

Cretaceogaster pygmaeus n. gen., n. sp. found in Canadian amber of Upper Cretaceous age from Cedar Lake, Man., is described and assigned to the subfamily Pachygastrinae of the Stratiomyidae. This is the first pre-tertiary record of this family.

Six species of predacious Miridae, common to apple trees in Nova Scotia, were used to develop laboratory rearing and feeding techniques for comparing the abilities of predators to consume prey. The test prey species was the European red mite, Panonychus ulmi (Koch), in the winter egg stage. The numbers of eggs consumed per day and per instar in the tests compared favourably with the known predatory values of these mirids under orchard conditions. Both sources of information were used to give the predators a tentative rating. The mirids Hyaliodes harti Knight, Diaphnocoris pellucida (Uhler), Pilophorus perplexus D. and S., and Blepharidopterus angulatus (Fall.) are effective predators, approximately equal to each other in ability to consume the winter eggs of the red mite. The two species Campylomma verbasci (Meyer) and Atractotomus mali (Meyer), which are phytophagous as well as predacious, were less voracious.The results indicate it may be feasible to develop a series of weighting factors, one for each stage of each predacious species, based on ability to consume prey.

The effect of temperature on the rate of development of Anax junius Drury was studied. Monthly larval samples were carried out for 2 years and laboratory experiments were conducted at constant temperatures. Field studies, at a eutrophic pond near Toronto, showed that in Canada populations of A. junius are not only maintained by migrants each year but also by residents. Two distinct populations were found, a summer (non-resident) population which developed from oviposition to emergence in approximately 3 months, from June to September, and an overwintering (resident) population which overwintered as half-grown larvae and developed in approximately 11 months from mid-July of one calendar year to the end of June of the next year. The former population was larger and comprised approximately 48% males and the latter was smaller and comprised approximately 41% males. A threshold temperature of development of 8.7° ± 0.1 °C was determined in the laboratory for the development of final-instar larvae of the summer population. The rate of development of final-instar larvae, reared at constant temperature, was similar to that of the entire summer aquatic stages which developed in fluctuating temperature. An average of 1332 degree-days ± 1% was required for development from the onset of oviposition to the onset of emergence of the summer population; whereas 20.5% more degree-days were required for the development of the overwintering population, employing the threshold temperature of 8.7 °C as determined for the summer population.It is recommended that correlation between degree-day totals and duration of larval development be used in further studies as a means for understanding the migration pattern and also the climatic limit of distribution for A. junius.

Pine root collar weevil damage is least on red pine plantations in cooler areas of northern Lower Michigan, and is inversely related to distance of the host from the nearest weevil infestation. Three hazard zones are suggested based on temperature. A high hazard zone occurs in the western part, a moderate zone in the central, and a low zone in the eastern part of the Lower Peninsula of Michigan.

A technique for rearing Hyssopus thymus is described by which easy observation of behaviour and development is possible. The life history and observations on paralysis, oviposition, host-feeding, and mating in this species are given. Complete development takes about 17 days at a constant temperature of 24 °C. Because H. thymus is common and widespread, shows no selection for attack at different tree crown levels, and has been responsible for up to 37% parasitism of overwintering Rhyacionia buoliana larvae, it is concluded that it is the most effective native parasite of R. buoliana in Ontario.

Attacks by Scolytus ventralis on white fir were correlated both with periods of low precipitation and with medium to heavy infestations of true mistletoe. Trees were seldom attacked when the "running mean precipitation" was above 54 in. Attacks were significantly more frequent and were often a year or more earlier on trees with substantial amounts of mistletoe. Broods were seldom produced, however.Data suggest that heavy mistletoe infestation rendered trees more susceptible to beetle infestation, possibly by creating moisture stress in infected trees.

Larvae of Neodiprion swainei Midd. were reared to the adult stage under controlled conditions of temperature and photoperiod. The effects of temperature are particularly evident during the larval stage, cocoon spinning, and adult emergence and are also observed through variation in cocoon weight and fecundity. Feeding, fecundity, and diapause are directly related to photoperiod. Larvae eat more when the photophase is long, an effect that is detrimental to the organism because there is a parallel loss of energy expressed in the number of day-degrees required to complete development.

Daily emergence of Scolytus ventralis Lec. from infested white fir bolts was highest in early afternoon (1200–1600 hours, P.D.S.T.) and limited to periods when air temperature exceeded 21 °C. More females than males emerged each day; the ratio in the total emergence was 1.9:1 and as high as 2.8:1 on warmest days. Flight occurred from mid-July to mid-September, with peak flight in mid-August. The intensity of flight activity was positively associated with varying temperatures above 24 °C (threshold).Visitation rates on lower boles of white firs were 10 times higher than those on Jeffrey pines. Two to three times as many beetles were trapped near girdled or severed white firs as about uninjured firs. Severed trees under attack by S. ventralis attracted three to seven times as many beetles as uninjured firs. When attack density reached 10 to 13 mines per sq. ft, the large number of beetles attracted in flight did not initiate mines in the trees already attacked but attacked surrounding host trees. Sex ratios of beetles trapped at experimental and control trees did not differ from that at emergence.

The Malpighian tubules of Hypoderma are endodermal in origin. There are two pairs, each pair uniting to form a common duct. The origin and distribution of the tubules in the first instar larva is different from that of the second and third instars; however, in these two later instars the pattern is similar. The lengths of the tubules in each stage of development depend on the degree of coiling. The musculature connecting the tubules, dorsal vessel, and hindgut are described.

The morphology and histology of the sex pheromone-producing gland in the females of Choristoneura fumiferana (Clemens), C. pinus (Freeman) (Tortricidae), and Malacosoma disstria (Hubner) (Lasiocampidae) is reported. A review of the literature relevant to such a study is presented in tabular form.

The sex pheromone of the female eastern spruce budworm was identified as trans-11-tetradecenal by a combination of electroantennogram techniques, laboratory bioassays, and chemical analysis. Subsequent field trapping showed that this compound is a potent attractant for both male Choristoneura fumiferana (Clem.) and C. occidentalis Free, thus supporting its identification as a sex pheromone of the eastern spruce budworm and suggesting that it is also a major component in the pheromone system of C. occidentalis.

Two new species of the genus Stenus Latr. (subgenus Hypostenus) are described: one from Quebec, the other one from Newfoundland.

Topical application of thiotepa on the adult male spruce budworm, Choristoneura fumiferana Clemens, at a concentration of 10 μg/insect resulted in 100% sterility. Unlike metepa, thiotepa did not have any apparent adverse effects on the competency of the sperms. Large numbers of male moths can be sterilized by allowing them to walk for 30 min on filter paper treated with a 2.5% solution of thiotepa in a 3:1 mixture of acetone and diffusion pump oil.

The presence of a sex pheromone was demonstrated in females of the 10-lined June beetle, Polyphylla decemlineata (Say). The pheromone, located in the female abdomen, was extracted with ethanol and with diethyl ether and was bioassayed in the field. Males responded to females at heights of 8–18 ft on trees, and to the extracted pheromone at heights of 6–12 ft on wooden stakes.

A new species of digamasellid mite, Digamasellus quadritorus, is described and illustrated. It occurs with Ips beetles under the bark of slash pine in Louisiana.

Ninety-six species of mites were associated with the southern pine beetle and allied scolytids in an outbreak area in Allen Parish, La. The complex was evaluated to ascertain which species may be of value as biological control agents.

One new genus, Phycoidella, and four new species, Cricotopus macraei, Cricotopus flannagani, Phycoidella dentolatens, and Lenziella cruscula are described in all stages. The genus Lenziella Kieff. is emended. The described species, three Orthocladiinae and one Tanytarsini, have many aberrant, but not necessarily apomorphic features.