Juvenile hormone, the secretion of the corpus allatum, apparently controls the secretory process of the male accessory glands of the yellow fever mosquito, Aedes aegypti. Topical application of a juvenile hormone mimic induces precocious and enhanced secretion. The treatment with the JH mimic not only increases the potency of males to inseminate more numbers of females, but also stimulates secretion in fully depleted glands of A. aegypti which under normal conditions do not renew the secretory process. Males whose accessory glands are depleted due to multiple matings and later treated with the mimic also inseminate. Cauterization of the corpus allatum complex has prevented the secretory function in the glands.

The name Enaysma Delucchi, 1954 is synonymized with the name Achrysocharoides Girault, 1913. Achrysocharoides is divided into two species-groups, guizoti and gahani. Fifteen North American species are recognized, including five that are new: A. reticulatus, A. bisulcus, A. albus, A. tetrapunctatus, and A. intricatus. A key to species, host lists, and distributions are included.

Forty exotic maize inbred lines from 10 countries with known resistance or susceptibility to the European corn borer, Ostrinia nubilalis (Hübner), were used to study the effect of plant resistance on borer survival from natural overwintering conditions and particularly the fecundity of the female moth during the following summer. Also, additional information was obtained on different biological characters of the insect. Resistant and susceptible lines were grouped according to their leaf feeding ratings (antibiosis), per cent borer survival at pollination time or at harvest (tolerance). Each specimen observed was kept on the same plant tissue until pupation. The number of eggs and egg masses/female was significantly higher only when lines are grouped according to their leaf feeding ratings. No significant differences were obtained in most biological characters of borers fed on resistant or susceptible maize lines: spring pupation, pupal parasitism, mortality and weight, moth emergence and sex ratio.

A population of the Douglas-fir cone moth, Barbara colfaxiana (Kft.), was studied on the Buckhead Seed Production Area, Lowell Ranger District, Willamette National Forest, Oregon, during 1971. Factors contributing to the mortality of B. colfaxiana are presented in a partial life table and discussed. The egg – instar I was identified as the critical age interval and resinosis the critical factor.

Larvae of three Nearctic species of Axonopsinae, Axonopsis setonensis Habeeb, Brachypoda cornipes Habeeb, and Woolastookia sp. near pilositarsa (Habeeb) are described, and diagnoses are proposed for the taxa involved. Observations on these larvae permit new insight regarding the phylogenetic affinities of Axonopsinae, thereby leading to a suggestion for reassessment of the supergeneric classification of the Aturidae.

Larval growth in B. terricola Kirby was measured from daily photographs of the combs of colonies. The growth rate of well-fed larvae was exponential until the commencement of cocoon spinning. No difference between the instantaneous growth rates of physiologically determined workers and queens developing in the same larval clump could be detected. Queen morphogenesis consisted principally of an extended stadial duration as compared with workers. Larvae which were starved regained their former growth rates once they were again fed plentifully. As a general feature of larval growth in Bombus it is suggested that the capacity to resume growth at an invariant maximal rate is retained under widely varying trophic regimes. Thus larval growth in bumble bees is interpreted as a succession of bursts of maximum proportional increase separated by periods of temporary starvation induced both by irregularities in colony food intake and the inherent stochasticity of worker feeding behaviour.

Field testing of a large number of synthetic compounds and several combinations of them revealed that male moths of the darksided cutworm, Euxoa messoria (Harris), were attracted to combinations of Z-7-hexadecen-1-yl acetate and Z-11-hexadecen-1-yl acetate. The most satisfactory attractants were combinations of these two compounds in ratios of 1:20 or 1:40. The presence of small amounts of the corresponding E-isomers did not interfere with the attractant. The diene, Z-7, Z-11-hexadecadien-1-yl acetate, in combination with Z-11-hexadecen-1-yl acetate also attracted the males, but there was no advantage in using the diene in place of Z-7-hexadecen-1-yl acetate.

Ingestion of a phenyl-benzoyl urea [1-(4-chlorophenyl)-3-(2,6-difluorobenzoyl)-urea] by Diprion similis (Hartig) interferes with molting. At the highest concentration (1% solution) tested, it prevents ecdysis but does not prevent apolysis. The Cuticle of pharate larvae is thinner than normal but the formation of melanin in the cuticle is not inhibited. At a concentration of.01%, ecdysis is usually completed but many survivors fail to feed following the molt. This failure is associated with the accumulation of a fibrous material in the midgut. Prior to the molt, food consumption as measured by faecal output is not impaired.

Benomyl or MBC phosphate incorporated into the meridic diet of eastern spruce budworm, Choristoneura fumiferana (Clem.), reduces the incidence of infection of adults by the microsporidian Nosema fumiferanae (Thom.). Some reduction in microsporidian levels is produced by 25 ppm benomyl; higher concentrations are more effective but even 250 ppm failed to reduce the incidence of microsporidia below 29% in a heavily infected stock. At benomyl concentrations of 75 ppm and above, budworm growth and fertility were reduced. The most notable effect of benomyl was the reduction of fertile matings and of percentage eclosion of eggs. Males were more sensitive to benomyl than females.

A study was made of the longevity and fecundity of Orgilus obscurator Nees and of the effects on longevity of feeding on various flowers. This parasite is pro-ovigenic, requiring little, if any, energy to develop its eggs, but the oviposition rate of 10 eggs per day requires a longevity of up to 3 weeks to utilize fully the potential of 160–200 eggs. Feeding on several species of flowers permits this longevity. The implications of the presence of these flowering plants within pine plantations for the success of parasites are discussed and the establishment and encouragement of Daucus carota L., Fagopyrum esculentum Moench, Asclepias syriaca L., and Nepeta cataria L. in plantations are recommended within the bounds of local weed control legislation.

The previously unknown biologies of three species of bud mining sawflies occurring in the central Sierra Nevada Mountains are compared. All three species oviposit in the buds of white fir, Abies concolor, but in different parts of the bud. Each has a different ovipositional posture as well. The first instar of each species mines the bud in a characteristic manner; later instar larval behavior is not distinguishable. The larvae cannot be separated morphologically, but the adults are easily recognized by their genitalia. At moderate population levels competition does not appear to be a major limiting factor even though the three species occupy the same niche. The feeding of Pleroneura aldrichi, P. koebelei, and P. lutea appears to have little if any effect on the host tree.

Ooencyrtus leptoglossi n. sp. is described and illustrated. This species is a parasite of the coreid bug (attacking pine seed) in Georgia, U.S.A.

Wasps of the genus Polistes have a number of characteristics that make them particularly suitable for studies on insect social behaviour. The females construct nests with exposed combs, have a reasonably complex social behaviour, and usually lack obvious morphological caste differences. In addition, the adults of many species establish colonies as groups of siblings (foundress associations), a method which is intermediate between colony founding by swarming, and colony founding by individual queens (Wilson 1971). Because of these characteristics, Polistes have been of interest to biologists who are concerned with the evolution of social behaviour in insects (e.g. Alexander 1974, Gibo 1974, Lin and Michener 1972, West 1967, West Eberhard 1969, 1975). Consequently, there is a need for a simple technique for rearing various species of Polistes under controlled conditions. Gibo (1974) briefly described modifications of Gillaspy's (1971) rearing method for P. apachus which made mass rearing of P. fascatus possible. This note describes the modified method in greater detail, and includes improvements that have resulted in increased yield and greater synchrony of colony growth. The improvements have been developed over 3 years and the method has been used to rear more than 100 colonies of various species of Polistes, including P. fuscatus, P. apachus, and P. dorsalis.

The new species of Elatophilus described herein was in the Anthocoridae collection of the late Mr. J. F. Brimley, Wellington, Ont. This collection of Hemiptera and Coleoptera was recently bequeathed to the Canadian National Collection of Insects, Ottawa.

DESCRIPTION. Adult. Male antennae simple, with short, fine cilia evenly and thickly distributed over the entire ventral areas. Palpi medium length. Forewing with ground colour light cream-grey. Antemedial and basal lines faint, grey-brown. Distinct wavy light line, divided by a fine postmedial line, formed between inner margin of subterminal area and outer margin of medial area. Terminal and subterminal areas combined into a grey-brown band with rust-brown spots between veins at the outer margin. Discal dot prominent. Hind wing pattern similar to that of forewing but more blurred. Wing expanse, with forewings fully extended, 20–22 mm.

During the summers of 1973 and 1974 examination of field collected samples of the spruce budworm, Choristoneura fumiferana, revealed the presence of a Pleistophora sp. (Wilson 1975). It has subsequently been determined as Pleistophora schubergi (Weiser 196 1 and pers. comm.). This microsporidium also appeared in laboratory cultures of the forest tent caterpillar, Malacosoma disstria. M. disstria is often infected in nature by the microsporidium Nosema disstriae. Preliminary tests were undertaken to compare the effects of these two microsporidia on the development of the forest tent caterpillar.

Mericia ampelus (Wlk.) was one of seven species of insect parasite reared from larvae of bertha armyworm, Mamestra configurata Wlk., that were collected in August 1972. At that time large populations of the host species were damaging plants of rape, Brassica spp., in numerous localities in western Canada (Wylie and Bucher 1977). As M. ampelus had not been reared before from M. configurata, studies were made in 1973–75 to determine the parasite's distribution and abundance, to obtain information on its biology and behaviour, and to assess its impact on populations of M. configurata.