In tests conducted in the McKinley River drainage, Alaska, seudenol combined with α-pinene attracted the most eastern larch beetles, Dendroctonus simplex LeConte. The next most attractive treatments included tamarack log sections infested with either unmated female D. simplex or unmated female Douglas-fir beetles, Dendroctonus pseudotsugae Hopkins, Neither frontalin nor trans- verbenol with α-pinene was attractive. Addition of niethylcyclohexenone (MCH) to the seudenol + α-pinene treatment repressed its attraction by 83%. Sex ratios of simplex responding to logs infested with female simplex or pseudotsugae were equal or favored females, but favored males in the case of seudenol + α-pinene. Addition of MCH shifted the sex ratio in favor of females. Two other scolytid species, Orthotomicus caelatus (Eichhoff) and Ips perturbatus (Eichhoff), were trapped, but were too few to relate to treatments. Two species of clerids were caught on traps: Thanasimus undatulus Say and Thanasimus dubius (L.); the latter is a new Alaskan record.

This study examined the effects of indoor fumigation with formic acid on survival of honey bee, Apis mellifera L. (Hymenoptera: Apidae), queens and varroa mites (Varroa destructor Anderson and Trueman (Acari: Varroidae)). A relationship between cumulative formic acid concentration and varroa mite mortality was established for colonies subjected to high-concentration fumigation while held indoors at 2–4 °C during winter. We also examined the effects of the formic acid release pattern and room ventilation rate on queen loss and treatment efficacy during fumigation. Two experiments were conducted in a wintering building. In both experiments, room air had higher formic acid concentrations than hive air. In experiment 1, 50% and 95% of mites were killed when exposed to in-hive concentration × time combinations of 49 ppm × days (CT50 product) and 111 ppm × days (CT95 product), respectively. No queen loss was observed under either the increasing-concentration or constant high concentration fumigation pattern. In experiment 2, 33% of queens were lost when minimum ventilation was used with room air concentrations of 57 ± 8 ppm (mean ± SE), whereas no queens were lost in controls or colonies exposed to room air concentrations of 27 ± 8 ppm with variable ventilation. Queen loss was associated with peak in-hive formic acid concentrations >20 ppm, but not with CT product, suggesting that queens are affected by acute rather than chronic exposure to formic acid. Formic acid fumigation significantly reduced the mean abundance of mites under both minimum- and variable-ventilation treatments.

The morphology and fine structure of the salivary syringe and its associated ducts of the six-spotted leafhopper, Macrosteles fascifrons (Stål), are described and illustrated from sections studied in the light and electron microscopes. Mycoplasma-like organisms (MLOs) were found in both the afferent and efferent ducts of the salivary syringe in insects transmitting aster yellows and in insects not transmitting the disease. The occurrence of MLOs proximal to the valve in the afferent duct proves that they were from the salivary glands and were not regurgitated from the gut or drawn in from outside the insect.

Larvae of species representing 8 genera of the family Aturidae from North America are described, including members of the genera Ljania, Neobrachypoda, Estellacarus, and Aturus for the first time adequately. Larvae of species of Woolastookia, Brachypoda, Axonopsis, and Albia are also described to provide comparative data for these genera. A key to the genera of Aturidae, and preliminary diagnoses for the family, currently accepted subfamilies, and genera are provided based upon larval characters. Information on host associations is reviewed for each taxon. Observations on morphology and host associations of larvae provide the basis for a discussion of the phylogeny of these genera, and a review of the classification of the family.

The frequent failure of parasite development beyong the immature stages during insectary rearing work often results in incomplete qualitative and quantitative data on insect parasites. Keys to the larval and pupal stages are therefore an extremely useful aid in completing the picture in a study of A parasite complex.

The following illustrated key makes it feasible to obtain reasonably accurate specific determinations of the puparia of the dipterous parasites of the spruce budworm, Choristoneura fumiferana Clem., that occur in Canada. The writer gratefully acknowledges the inspiration and co-operation of A. R. Brooks during the preliminary preparations for the key. The illustrations were executed by Miss M. MacKay (Figs. 1-14) and R. Sugden (Fig. 15). Each figure illustratis the following: (a) posterior aspect of a puparium showing the location of the stigmal plates and the anal aperture, and any protuberances that are present; (b) one stigmal place and the stigmal slits; (c) lateral aspect of the outline of a puparium.

The feeding habits of Melanoplus bivittatus (Say) and M. femurrubrum (DeGeer) in an Ontario grassland were investigated by analyzing crop contents. The study revealed that both species are mixed feeders which prefer forbs over grasses. Both species ingested a wide range of host plants in the field, showing preferences for some species over others. Differential growth and mortality resulted when grasshoppers were reared on different host plants.

On the basis of data obtained during a light-trapping survey in western North America, noctuid moth activity appears to be influenced by nightly temperatures but not by lunar periodicity.

Average fecundity of free-living and caged female Psylla pyricola Foerster on pear trees was reduced by high summer temperatures and low host vigor. Implications of these observations in the planning of control programs is discussed.

A sample of 205 specimens of the declarata group of the genus Euxoa was subjected to clustering, principal components, and discriminant analyses. The analyses were based largely on male genitalic characters. Only the discriminant analysis was successful in segregating the three nominal components of the group.

Baetis bundyi new species is described from nymphs which were collected from tundra ponds in the central Canadian arctic (62.45 N., 94.27 W.). Based on measurements of a series of nymphs the eggs must hatch in early July and adults emerge in August. A table is presented for separating this species from other known arctic Baetis.

It was of interest but no great concern when the finding of Musca autumnalis DeGeer in Nova Scotia was reported by Vockeroth (1953). Previously, M. domestica Linnaeus was thought to be the only species of the genus present in North America. Two previous reports of M. autumnalis as corvina (Walker, 1849, 1871) were thought to be misidentifications.

Diplolepis rosaefolii (Cockerell) induces a lenticular gall on the leaves of various roses across Canada. In Ontario and Quebec, D. rosaefolii is found only on Rosa acicularis Lindl., and its galls are inhabited by eight species of parasitoids, the most common being Chrysocharis pentheus (Walker), Orthopelma luteolator (Gravenhorst), and Eupelmus dryorhizoxeni Ashmead. Parasitoids and the inquiline Periclistus sp. make up 48–62% of gall inhabitants. Here we report a population of D. rosaefolii on the hybrid rugosa shrub rose Thérèse Bugnet in a field of experimental roses in Quebec. Only two species of parasitoids and one specimen of Periclistus sp. were associated with these galls.

The susceptibility of first-instar cabbage maggot, Delia radicum (L.), to parasitism by seven strains or species of entomogenous nematodes was compared in Petri dishes lined with moist filter paper. The effective doses for 50% mortality (ED50) of the Mexican, Breton, and All strains of Steinernema feltiae Filipjev, of S. bibionis (Bovien), and of Heterorhabditis heliothidis (Khan, Brooks, and Hirschmann) ranged from 98 to 341 infective juveniles per host larva with overlapping 95% confidence intervals; the slopes ranged from 1.36 to 1.07. The DD136 strain of S. feltiae and the species H. bacteriophora Poinar were significantly less lethal with ED50 values of 1113 and 1719 nematodes per host larva, respectively. The addition of a thin disc of rutabaga into the test dishes increased ED50 values by a factor of 20 or more. Application of the Mexican strain of S. feltiae at 5 × 105 nematodes per plant to small caged field plots of rutabaga artificially infested with eggs of D radicum provided control similar to that with diazinon applied at 1.4 L AI per hectare. Practical control of D. radicum on rutabaga with entomogenous nematodes would require strains or species considerably more lethal than those tested here.

Complex subsociality involving guarding, progressive provisioning, and trophic egg production behaviours in herbivorous Hemiptera is known in only a few genera in the Cydnidae subfamily Sehirinae and in Parastrachiidae. Because progressive provisioning and trophic egg production are apparently specific to these closely related species, phylogenetically it seems likely that the behaviours emerged once in the common ancestor of this clade. However, the scarcity of information on species in the clade precludes any reliable exploration of this hypothesis. To ameliorate this situation, it is necessary to accumulate additional information for as many related species as possible. To this end, we first targeted Japanese representatives of the genus Adomerus Mulsant and Rey (Hemiptera: Cydnidae), three species of which are distributed in Japan. Complex subsocial behaviours in two of these species, Adomerus triguttulus (Motschulsky) and Adomerus variegatus (Signoret), have been well characterised and analysed. The third Japanese species, Adomerus rotundus (Hsiao), was identified to display complex maternal care, but, with the exception of egg hatch synchronisation, parental behaviours have not been characterised. In this study, we examined the parental behaviours of A. rotundus. Additional investigations on subsocial behaviours, in addition to morphological and molecular analyses, should gradually clarify whether the complex subsociality represents a homologous or convergent adaptation.

Many fruit producers use commercial colonies of Bombus impatiens Cresson (Hymenoptera: Apidae) to supplement crop pollination by native bees. A small number of Newfoundland (Newfoundland and Labrador, Canada) farmers forego purchasing new colonies and, instead, purchase previously used colonies from crops in other provinces. This practice has potentially dangerous implications that may adversely affect future native bee diversity in Newfoundland. This study is the first to record the presence of native bumble bee species inside the colonies of new and pre-used commercial B. impatiens and the first to look at diseases in native bumble bees from Newfoundland. Polymerase chain reaction and taxon-specific oligonucleotides were used to screen the commercial and native bumble bee species for pathogens. Crithidia bombi (Lipa and Triggiani), Apicystis bombi (Liu, Macfarlane, and Pengelly), Nosema bombi Fantham and Porter, Nosema ceranae Fries et al., and species of Ascosphaera Olive and Spiltoir, were detected in native bumble bees that were collected from inside the new and pre-used commercial B. impatiens. Crithidia bombi, A. bombi, and N. bombi were also detected among native bees that were collected away from the commercial colonies. Nosema apis (Zander) and Melissococcus plutonius (White) were not detected in any of the bees tested. The mixing of native bumble bees in B. impatiens colonies increases the potential for pathogen spillover and spillback that may threaten the small and vulnerable island bee fauna.

The disruption of chemical communication between adult insects by the use of synthetic sex pheromones is an attractive method of insect control. However the mechanism of disruption is not clearly understood. It is generally considered that 3 mechanisms are in operation (see review by Bartell 1982): masking of the natural-pheromone plumes by permeation of the atmosphere with synthetic pheromone; orientation of males to false trails; and habituation of the central nervous system by prolonged or repeated exposure to the pheromone. The relative importance of these 3 mechanisms in disruption is of concern, as this can affect the strategy for disseminating the pheromone.

The sunflower moth, Homoeosoma electellum (Hulst) is a constant and damaging pest of cultivated sunflowers in Texas, Nebraska, and California. It was reported in Canada from Manitoba and Saskatchewan as early as 1936. Present studies begun in 1975 show that it can cause economic damage to cultivated fields in Saskatchewan. Field observations also indicate that this pest does not overwinter in Canada but that adults fly, or are blown in, from the south each year.

An efficient method of rearing this pest in the laboratory was developed and observations on its life history and behaviour, especially courtship and mating behaviour, are reported herein.

The genus Dyschirius includes 56 North American species which are arranged in 13 species groups. Keys are provided for the species groups and the species. Four new species are described: D. sculptus Bousquet (type locality: Pass-a-Grille Beach, Florida); D. ferrugineus Bousquet (type locality: Goose Island State Park, Texas); D. larochellei Bousquet (type locality: 6 mi. S Lake Placid, Florida); and D. comatus Bousquet (type locality: Highlands Hammock, Florida). Six species names are placed in synonymy for the first time. They are (with the junior synonym listed first): D. arizonicus Van Dyke 1943 = D. interior Fall 1922; D. duplicates Fall 1901 = D. affinis Fall 1901; D. desertus Fall 1925 = D. perversus Fall 1922; D. subpunctatus Hatch 1949 = D. sphaericollis (Say 1825); D. basalis LeConte 1857 and D. transmarinus Mannerheim 1853 = D. integer LeConte 1851. The adult and larval character states of the genus are listed and comments are provided for each species group.

Furia gastropachaecomb. nov. (= Furia crustosa MacLeod et Tyrrell) has long been associated with declines in populations of the forest tent caterpillar, Malacosoma disstria Hübner; however, its prevalence and impact on host populations have never been documented. We clarify the nomenclature for this species, which has previously been called F. crustosa, and describe the morphology of F. gastropachae isolates from Maryland and New York. Epizootics of F. gastropachae were studied in M. disstria populations in New York and Maryland, United States of America. Prevalence (mean ± SE) of F. gastropachae in late fifth instar larvae in New York was 25.6 ± 7.8% compared with 22.2 ± 11.3% infection by virus and 23.3 ± 8.4% parasitism. In Maryland, F. gastropachae was not found in early instars and its incidence in fourth and fifth instars was 14.5 ± 7.3 and 21.6 ± 17.6%, respectively. Dipteran parasitoids were also important natural enemies with 38.3 ± 3.0 and 17.9 ± 1.4% parasitism in fourth and fifth instars, respectively. Virus was found in fewer than 5% of larvae collected. Furia gastropachae showed a marked tendency toward resting spore production in infected larvae, with 100% of larvae collected in New York and >80% of larvae collected in Maryland producing resting spores, either alone or in combination with conidia. The appearance of cadavers of larvae dying from fungal and viral infections was similar. Of 13 species of Lepidoptera exposed to F. gastropachae conidia in host-range bioassays, only 3.3% of Danaus plexippus (L.) (Lepidoptera: Danaidae), 5.6% of Pieris rapae (L.) (Lepidoptera: Pieridae), and 3.7% of Manduca sexta (L.) (Lepidoptera: Sphingidae) were successfully infected by this fungus.

Dosage–response relationships of seven insect growth regulators (IGRs) to last instar western spruce budworm, Choristoneura occidentalis Freeman, were determined by topical application, spray application, and diet incorporation bioassays. Mortality was defined as failure to emerge as a viable adult. In spray application experiments, four IGRs—ZR-512, ZR-619, ZR-1662, and Ro 10-3108—had LD50s of less than 70 g/ha (1 oz/acre). Relative lethal effectiveness, based on a simple model combining data from the three bioassays, was ZR-1662 > ZR-619 > ZR-512 > Ro 10-3108 > ZR-777 > ZR-587 > ZR-515. We concluded that several IGRs, applied to a population consisting primarily of last instars, would induce lethal effects at dosages comparable to dosages of several conventional insecticides.