The sex pheromone of the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), from the Niagara Peninsula, Ontario, was investigated using chemical analysis, GC–EAD, and field trapping experiments. The pheromone gland contained: (Z)-11-tetradecenyl acetate (Z11-14:Ac), (E)-11-tetradecenyl acetate (E11-14:Ac), (Z)-11-tetradecen-1-ol (Z11-14:OH), and (Z)-11-tetradecenal (Z11-14:Al). The average amounts of Z11-14:Ac, E11-14:Ac, Z11-14:OH, andZ11-14:Al were 40.40, 0.83, 0.47, and 0.13 ng/female, respectively. Eight other structurally related compounds, (E)-11-tetradecenal (E11-14:Al), (E)-11-tetradecen-1-ol (E11-14:OH), pentadecan-2-one (15-2kt), hexadecanal (16:Al), hexadecan-1-ol (16:OH), heptadecan-2-one (17-2kt), octadecanal (18:Al), and octadecyl acetate (18:Ac), were also identified. In a field trapping experiment, adding Z11-14:Al to lures containing a 100:3:5 blend of Z11-14:Ac, E11-14:Ac, and Z11-14:OH in an amount equal to 2% of the main component significantly increased the number of moths captured in apple, Malus domestica (Borkh.) (Rosaceae), orchards. The removal of Z11-14:Al from lures containing a 100:2:1.5:1 blend of Z11-14:Ac, E11-14:Ac, Z11-14:OH, and Z11-14:Al resulted in a > 50% reduction in the average total number of moths captured in a trap. This study provides the first evidence that Z11-14:Al is present in the pheromone of an eastern North American population of C. rosaceana.

Effective codling moth control was obtained by timing the application of insecticidesito coincide with the period of greatest larval emergence in the orchard. This occurred 6–10 days after first emergence and the latter could be predicted by heat unit summations. In 1971 and 1972 144 and 137 degree-days accumulated from the date on which the first male moth was taken in pheromone traps and the first larvae emerged, respectively.

Hygro-receptive sensilla have been found on the antennae of fruit flies (1), spider beetles (2), cockroaches (3), wireworms (5), ticks (6), mealworm beetles (8), flour beetles (11), and body lice (16). Two types of antennal sensilla, the basiconic and the coeloconic, have been identified as hygro-receptors of the grasshoppers, Melanoplus differentialis (Thos.) and M. mexicanus mexicanus (Sauss.) (12, 13). This paper describes the antennal sensilla of Melanoplus bivittatus (Say) and discusses their function.

Psithyrus spp. (Hymenoptera: Apidae) are obligate social parasites of bumble bees (Bombus spp.). Morphological and physiological features of P. ashtoni (Cresson) females, which may facilitate the successful usurpation of host nests, were examined. Parasite females were no larger than B. terricola Kirby queens, although they possessed a number of protective modifications to the exoskeleton, as well as increased offensive armament, including larger mandibles and a longer venom gland. Females of P. ashtoni and P. insularis (Smith) possessed a greater number of ovarioles than host queens, and produced smaller eggs. The Dufour’s glands of the two Psithyrus species were significantly larger than those of B. terricola. There appears to have been considerable convergence in the evolution of socially parasitic lifestyles in bumble bees and wasps (Vespula spp.), presumably as a consequence of similar selective pressures operating on parasites belonging to these distantly related but socially similar taxa.

The eggs and oviposition sites of six species of predatory mirids from Nova Scotia apple orchards are described. These species are Hyaliodes harti Knight, Atractotomus mali (Meyer), Deraeocoris fasciolus Knight, Diaphnidia pellucida Uhler, Blepharidopterus angulatus (Fall), and Pilophorus perplexus D. & S. The differences between the eggs of each species are great enough to identify them in situ.

Effects of soil moisture, texture, and temperature on larval and pupal survival and development of the bean leaf beetle, Cerotoma trifurcata (Forster), were investigated in laboratory and greenhouse studies. In both cases, mortality rates were highest during the first instar, decreased during subsequent larval instars, then increased during the pupal stage. Under constant laboratory conditions, survival and adult weights were highest in wet and organic soils and lowest in dry and loamy sand soils. In wet and organic soils, developmental time was shorter than in other soils.

Although survival/plant in the greenhouse was greatest in sandy clay loam, survival/nodule was greatest in organic soil.

These studies, together with oviposition preference, egg survival, and larval movement experiments agree with field observations and provide some explanations for observed patterns of local and regional abundance of the bean leaf beetle in North Carolina.

At every turn, since beginning my studies in the aquatic Hemiptera some four years ago, my attempts to verify some observation have been balked by the extreme meagreness of the information on the subject running all through the field of entomological literature. This lack is far more noticeable with reard to the immature stages of the Cryptocerata and of the aquatic and semi-aquatic forms of the Gymnocerata.

Anti-attractants, defined as substances with little or no intrinsic repellency but with the property of diminishing the attractiveness of a lure, are predicted on spectroscopic grounds and their existence demonstrated in experiments with Ceratitis capitata (Wiedemann), and Dacus cucurbitae (Coquillett).

Eggs of Hexagenia rigida McDunnough transferred directly from 20° to 36°, 32°, 28°, 24°, 20°, 16°, 12°, and 8 °C were monitored for start of hatch, hatching rate, success of hatch, and hatching period. Eggs did not hatch at 36 °C or 8 °C. There was a direct relationship between temperature and start of hatch (from day 7 at 32 °C to day 77 at 12 °C). Over 90% hatch occurred at all temperatures except 12 °C. Hatching periods ranged from about 6 days at the higher temperatures to over 80 days at 16 °C and 12 °C. Hatching occurred at 36 °C when eggs were transferred in increments of 4 °C every 2 days.Storage capabilities of eggs in "early", "middle", and "late" stages of embryonic development were tested at 12 °C and 8 °C using a direct or stepwise transfer method. Hatching parameters monitored were hatch rate, success of hatch, and hatching period up to 90% hatch of total number of eggs. Middle stage eggs transferred in a stepwise manner could be held at 8 °C for up to 52 weeks with least effect on hatching parameters. Middle and late stage eggs could be stored for up to 16 weeks at 8 °C using the direct transfer method, and early stage eggs, which were affected most by cold storage, could be held for 2 days at 12 °C with minimal effect on hatching parameters. The storage of eggs, shown here to be possible, is potentially useful for providing such material for bioassays throughout the year.

Single aerial applications of Bacillus thuringiensis Berliner (Bt) to control infestations of the eastern spruce budworm (Choristoneura fumiferana Clemens) have had varied operational success. Double applications are too expensive for general use, but might prove useful if directed to areas where the initial application was unsuccessful. This requires forecasts of the efficacy of the initial application in operational spray blocks within 4–5 days.

Data were collected in 30 spray blocks in 1989 in a feasibility study to determine if such forecasts of spray efficacy could be made from the prespray budworm population density, N0, and from the proportion of the population that had ingested a lethal dose Bt within 2 days of application, M. A mathematical model forecasting the postspray budworm population density, NF, was derived from population-dynamic considerations and fitted (r2 = 0.48, p < 0.0001):

The proportion of current foliage defoliated, D, depended (r = 0.81) on N0 and on whether the block was sprayed (I = 0) or not (I = 1):

Only one measure of defoliation involved M in any statistically significant way. The predicted (from values of N0) proportion of defoliation prevented by Bt application, dD, was weakly (r2 = 0.25, p = 0.002) related to M:

The large proportion of the variation in efficacy that remains unexplained by the models involving M limits the operational utility of this approach as it now stands for specific sites. The potential for further development of these models as decision support tools for fairly large spray blocks is discussed in terms of improving the sampling plan and including additional predictor variables.

Methods are also presented that reduce bias in calculations of population reduction (Abbott 1925) and foliage protection when data are available from few control and many treatment blocks.

The tribe Xyloterini is widely distributed in the Holarctic realm. It is comprised of three rather small but well known genera. The largest of these, Trypodendron Stephens, consists of about a dozen species and occurs throughout the Holarctic realm; five of these species occur in North America. Dendrotrypum Schedl contains six species that are known only from eastern Asia. Xyloterinus Swaine contains one species from eastern North America.

Stethynium Enock, a mainly old world genus most of whose members occur in Australia, is redescribed based on study of the non-Australian species. The subgenus Neostethynium Ogloblin is removed from Stethynium and given generic status. The names S. faunum Girault and S. empoascae Subba Rao are synonymized under S. triclavatum Enock. A lectotype is designated for S. triclavatum. Stethynium angustipennesp. n. is described.

Schizophragma Ogloblin, formerly a subgenus of Patasson, is redescribed as a genus. Anaphes bicolor Dozier and Stethynium annulatum Doutt are transferred to Schizophragma. The names S. annulatum and S. nana Ogloblin are synonymized, respectively, under S. bicolor and S. parvula Ogloblin. Lectotypes are designated for S. bicolor (Dozier) and S. latipennis (Crawford). A provisional key to the species of Schizophragma is presented.

The species of Macroneura Walker are revised for America north of Mexico. Seven species are recognized, of which M. camptoptera, M. cerasma, M. chrysosinamora, and M. tanyaris are described as new; M. meteori (Gahan) is removed from synonymy with M. epicaste (Walker) and accorded specific status. Eupelmus melanderi Brues is synonymized with Eupelmus dryorhizoxeni Ashmead and the taxa are reassigned to Eupelmus Dalman from Macroneura. Diagnostic features are given to distinguish females and males of Macroneura from members of other eupelmine genera; putative phylogenetic relationships of Macroneura are discussed, and a key is presented to distinguish females and known males of the North American species.

The genus Hoploseius is redefined on the basis of H. cometa (Berlese), H. drosophili (Chant) new combination, and H. bakeri new species, which are described, keyed, and illustrated. Fragmentary ecological data with specimens of Hoploseius make it apparent that the mites are associated with polyporous bracket fungi and have a phoretic relationship with adult drosophilid flies.

Previous work described the effects of predation of pea aphids by adult coccinellids. That work has been extended to cover the entire reproductive cycle of the coccinellids. The relationship between amount of aphids eaten, and numbers of coccinellid eggs produced, was determined in the laboratory and used to predict numbers of eggs produced in the field. The survival rate of the eggs to adults, as a function of aphid density, was estimated in large field cages and in small enclosures. These relationships were incorporated into a population model for both predators and prey. The model has been validated against field data. It suggests that predator reproduction is optimized when conditions are very good. The significance for optimal foraging theory and biological control is discussed.

A key is given for 4 subgenera in the aphid genus Uroleucon Mordvilko in America north of Mexico. An annotated list and keys are presented for 44 species of the subgenus Uroleucon, 12 species of the subgenus Uromelan Mordvilko, and 1 species of the subgenus Satula Olive. Nine new species are described in the subgenus Uroleucon: Uroleucon (Uroleucon) alaskense n. sp., U.(U.) arnesense n. sp., U.(U.) boreale n. sp., U.(U.) chani n. sp., U.(U.) deltense n. sp., U.(U.) elephantopicola n. sp., U.(U.) ivae n. sp., U.(U.) maximilianicola n. sp., and U.(U.) vancouverense n. sp. Two subspecies, U. (Uromelan) illini subspecies crudae and sangamonense, are listed here merely as color forms of illini (Hottes and Frison), not subspecies. Uroleucon (Uroleucon) muralis Buckton, U. (Uromelan) compositae (Theobald), and U.(U.) solidaginis (Fabricius) have been listed as present in North America, but there appear to be no authentic records of their occurrence. Uroleucon (Uroleucon) pseudochrysanthemi (Olive) is declared to be a synonym of U.(U.) lanceolatum Patch, and U. (Uromelan) squarrosum (Sanborn) as a nomen dubium.

Although the extreme winter conditions of Arctic habitats are considered to be important determinants of the faunal composition of Arctic regions, the overwintering biology of most Arctic insects is unknown. A significant proportion of the insect fauna at high latitudes are hymenopterans, yet little information is available on their overwintering strategies. In this study I examined the overwintering strategies of willow gall-forming and catkin-feeding nematine sawflies and their parasitoids. All sawfly species overwintered as prepupae, were freezing-tolerant, and survived exposure to −50 °C. Freezing at high subzero temperatures was initiated by ice nucleators associated with the posterior hind gut wall. Heterogeneity of overwintering habitats with respect to temperature was not a determinant of the overwintering success of these Arctic sawflies. Divergent overwintering mechanisms were evident in the sawfly parasitoid taxa. Endoparasitoid larvae, like their sawfly hosts, were freezing-tolerant. Freezing of immature, feeding endoparasitoid larvae occurred at the freezing point of the host prepupa and was a consequence of the inoculation of the endoparasitoids' fluid compartments by ice crystals growing in the host hemolymph. Peculiarities in the structure of the endoparasitoid larval gut suggest that the site of nucleation is across the gut wall. Outside their hosts, however, endoparasitoid larvae can supercool extensively, and their tolerance of extremely low temperatures is similar to that of their hosts. Overwintering strategies adopted by the ectoparasitoids were also diverse, with both freezing-tolerant and freezing-intolerant species present in the parasitoid community. Freezing-intolerant species could not survive winter temperatures in the field in the absence of an insulating layer of snow.

Observations mainly on sexual behavior were made in both the field and laboratory on five species representing four genera of stag beetles all occurring in central Illinois.Males of Lucanus Scopoli (= Pseudolucanus) and Dorcus MacLeay which have relatively short mandibles made direct use of these appendages in subduing and maintaining the female in position during mating.Males of Platycerus Geoffroy and Ceruchus MacLeay which have larger mandibles did not use these appendages to hold the female, but rubbed a pair of legs intermittently against the female’s elytra and had much longer matings.The presence of a female stimulus was determinant in the amount of fighting among males.

A strain of Bacillus cereus (Pr-1017) was isolated from dead and dying larvae of the larch sawfly. Laboratory and field feeding tests resulted in mortalities as high as 60 per cent and 38 per cent, respectively.

A positive correlation between the incidence of mortality and the mean daily temperatures was obtained in the field experiments.

Immature stages of the rodent bot fly, Cuterebra tenebrosa Coquillett, from central Washington are described and illustrated. Redescription of both sexes of the adult fly are also provided. Larval cuticular spines and posterior spiracular patterns are distinctive for second instars. Important characters of third instars include shape and number of points on cuticular spines and papillae arrangement. C. tenebrosa parasitizes bushy-tailed wood rats (Neotoma cinerea) and desert wood rats (N. lepida) in the western United States and western Canada.