It has been shown that Drosophila melanogaster fly to the source of an attractive scent by making a series of highly stereotyped responses to olfactory and visual stimuli (Kellogg, Frizel, and Wright, 1962). The comparable processes by which Aedes aegypti are guided to a warm-blooded host have now been studied and are the subject of this paper.

The multiporous plate sensillum occurs on the antennae of Hymenoptera. The internal and external cuticular surfaces of these sensilla, as well as the cellular ultrastructure, were examined in the Braconidae by electron microscopy. The sensillum has an elongated, external, porous plate and an inner, cuticular septum in which there is an aperture. It is innervated by numerous neurons, the dendrites of which pass through the aperture, branch and traverse the longitudinal axis of the sensillum. The ratio of aperture length to sensillar length was measured on the internal cuticular surface in 32 species. This ratio increased from the ancestral to the derived species. This sensillar character may be useful in elucidating braconid systematics. It also has potential use in the systematics of other hymenopterous parasitoids.

The European corn borer, Ostrinia nubilalis (Hübner), has two distinct geographical populations in southwestern Ontario. The time required for diapause termination is the main distinguishing feature. This together with different critical photoperiods for diapause induction explains the occurrence of two complete generations in the southern portion and only one in the northern portion of this region.

We examined mate-finding behaviour in Agrilus subcinctus Gory (Coleoptera: Buprestidae) and Agrilus cyanescens Ratzeburg (Coleoptera: Buprestidae) in ash (Fraxinus L. (Oleaceae)) stands in the Great Lakes region of the United States of America. Dead specimens of both species were affixed to ash foliage to serve as models to test visual stimulation of aerial attraction of males. The models were washed in dichloromethane to remove cuticular lipids or were left unwashed, to test for the presence of close-range pheromonal cues. Males of both species located females via a visually guided aerial approach from up to 1 m above females, similar to the behaviour of Agrilus planipennis Fairmaire. When male A. subcinctus or A. cyanescens made contact with females, contact sex pheromones mediated subsequent copulation behaviour. During their visually mediated airborne descent and landing, male A. cyanescens landed directly on female models; whereas, male A. subcinctus landed significantly more often on the leaf surface supporting a model. Male A. subcintus performed precopulatory pounce behaviour on female models after assessing surface chemical cues with their antennae. Male A. cyanescens landed upon a variety of models, but after landing, rejected a significant proportion of models lacking female A. cyanescens cuticular lipids.

Ants (Hymenoptera: Formicidae) are ubiquitous and of considerable ecological interest, yet poorly studied in Canada. Given their natural history attributes and relatively low density and diversity in cool boreal forests, there is a need to evaluate the applicability of commonly used approaches to sampling and analysis. We examined the relative utility of two pitfall trap designs, mini-Winkler litter extractions, and colony versus forager sampling for ecological studies. First, we found that Laurent (conventional) and Nordlander (modified to exclude larger nontarget organisms) pitfall traps were equally efficacious for estimating total species richness. Second, pitfall trapping yielded marginally higher total species richness than mini-Winkler litter sampling, by the incidence-based estimator (Chao2). Third, two studies considering the relationship between captures of individual ants in pitfall traps and identified ant colonies argued for caution in how pitfall captures are interpreted. In the first study, Nordlander traps placed in a grid surrounding nests of Formica obscuripes Forel revealed unique and highly patchy captures of individuals, with no patterns relating to proximity to the nest. In the second study, abundance estimates to compare ant assemblage structure in a simple grassland ecosystem by pitfall trapping (relative) and area-based hand sampling (absolute) for colonies, revealed that relative sampling does not reflect the absolute ant assemblage structure. Our results support, equivocally, the use of pitfall traps (Nordlander) over mini-Winklers in the cool moist forests of west-central British Columbia, but individual specimen counts should not be used when analysing the data.

Twenty-one species of Coccinellidae were trapped in flight between 0.8 and 14.3 m from 1992 to 1995 in New Brunswick, Canada. Catches were larger at 0.8 m, with a rapidly decreasing capture rate leading, on average, to more than 50% of the catches at or below 3.8 m every year. The capture rate at 14.3 m was lower than at any of the nine other levels. Hippodamia convergeas Guérin-Méneville flights were distributed close to the ground, with more than 50% of catches at 0.8 m, whereas Mulsantina hudsonica Casey flights were similar at all levels. The strong decreasing gradient of flight as a function of height for Coccinellidae (−0.825) was strongly influenced by that of H. convergens (−1.809) and of Coccinella septempunctata L. (−0.921) and Coccinella trifasciata perplexa Mulsant (−0.715). All other species had a slope of less than −0.5. The temporal distribution of flights was species specific, with maximum activity before the end of June for most, but this was not reflected in the frequency of catches for the entire family, which did not differ throughout the season, although they tended to be lower after mid-August. The weekly vertical flight distribution differed from the average distribution pattern only occasionally, probably during periods of long-distance dispersal. These profiles and known catches from a single trap location can be used to estimate dispersal activity at different heights.

Almost 100 years have passed since J.M. Swaine, the assistant entomologist in charge of Forest Insect Investigations, wrote, “Canadian bark-beetles: a preliminary classification, with an account of the habits and means of control”. The goal was to “put into the hands of practical foresters information of inestimable practical value… to prevent the continued loss of timber now being destroyed” by “the most insidious enemies of the forest”. In this paper, we celebrate Swaine’s pioneering work by summarising the foundational aspects of his early treatise of 1918: the “general habits” of bark beetles, classifications of their behaviour, causes of population increase, and mitigation tactics. In the founding text, Swaine identified all major Dendroctonus Erichson (Coleoptera: Curculionidae) bark beetles found in Canada, although details on life histories were scarce. We summarise current knowledge of the life histories and population dynamics of the spruce beetle, D. rufipennis Kirby; the Douglas-fir beetle, D. pseudotsugae Hopkins; the eastern larch beetle, D. simplex; and address the current range expansion of mountain pine beetle, D. ponderosae Hopkins. We review how aspects of global change, such as invasive species, have altered the population dynamics of certain bark beetles. Finally, we conclude with lessons from two of the many past contributors to bark beetle ecology in Canada, J.M. Swaine and H.A. Richmond.

The Canadian registration in 2007 of Disrupt SBW Micro-Flakes®, a pheromone-based product for control of spruce budworm, Choristoneura fumiferana (Clemens), paved the way for large-scale trials to test the practicality of mating disruption as a commercial pest management strategy. We review results from field and laboratory experiments on pheromone-based mating disruption of spruce budworm conducted from 1974 to 2008. Application of pheromone from the ground or the air consistently reduced the orientation of males toward pheromone sources. Mating disruption also reduced the mating success of caged or tethered females in 15 of 16 field studies where this parameter was recorded, but had only a limited effect on the mating success of feral females. No consistent difference in the density of egg masses in control and treated plots was observed, which has often been attributed to immigration of gravid females into pheromone-treated plots. Laboratory studies suggest that false-trail following is the predominant mechanism underlying mating disruption in spruce budworm. The enhanced mating success of females with increasing population density suggests that mating disruption should target low-density emergent populations during the initial phase of an outbreak. Constraints that may limit the potential of mating disruption as a management tool include (1) difficulties associated with obtaining accurate sampling estimates at low population density to forecast the onset of outbreaks, (2) potential behavioral adaptations by which females enhance their mating success when the atmosphere is treated with pheromone, and (3) long-range dispersal of females by flight.

On 12–13 July 1964, forest tent caterpillar, Malacosoma disstria Hübner, adults were carried southward from an outbreak in the forested area of central Alberta for at least 300 miles by the turbulent air associated with a cold front. Details of the area of dispersal and the weather system responsible are given.

The following behavioral patterns of three chalcidoid parasites, Monodontomerus obscurus, Pteromalus venustus, and Melittobia chalybii, were compared in the laboratory: feeding by adults, precopulatory routines, copulating, anesthetizing the host, ovipositing, mobility of the larvae, cannibalism among larvae, overwintering, diapause, life cycle, and the ability of a host to support a parasite.

The factors responsible for the relative resistance of plants to aphid attack are not very well known. Chemical analyses of several varieties of peas indicate that the quantity of nitrogenous constituents in plant juice is proportional to the susceptibility of the plant to aphid attack. These tests hare also demonstrated that amino acids represent the major portion of the soluble nitrogenous constituents in the plants studied.

By the method of paper partition chromatography, several qualitative and semi-quantitative analyses were made of the amino acids in juice extracts of two varieties of peas and of pea aphids feeding on these varieties. This particular method of chromatography, first developed in England in 1944 by Consden, Gordon, and Martin (1), and modified since by other workers (2, 3), was found very effecrive for these studies.

The innervation of a pregenital, the genital, and postgenital segments of the male and female of Schistocerca gregaria (Forskäl) is described in detail and is compared with other orders of the Insecta.

A model of predation by Podisus maculiventris (Say) on Mexican bean beetle, Epilachna varivestis Mulsant, larvae in soybeans is presented. The attack equation described the number of prey attacked as a function of the number of prey, soybean leaf area, and the search behavior of the predator. The area searched by P. maculiventris was related to the amount of leaf area and the number of prey. Predictions of the number of Mexican bean beetles attacked per predator were compared with an independent field data set. The relevance of the predation model to studies of predation in other agricultural systems is discussed.

Simulium (Simulium) acrotrichum Rubtsov, a black fly from Central Asia, provides a platform for examining the evolutionary relationships of selected species groups in the subgenus Simulium Latreille. The female, male, pupa, and larva of S. acrotrichum are properly associated and morphologically redescribed and illustrated. The banding sequence of the larval polytene chromosomes is compared with that of the Simulium subgeneric standard, from which it differs by nearly 30 fixed rearrangements. Structural and chromosomal features indicate that S. acrotrichum is the sister species of S. flavidum Rubtsov. Simulium acrotrichum can be placed confidently in a group consisting of the S. malyschevi Dorogostaisky, Rubtsov, and Vlasenko and S. reptans (L.) groups, which are part of a larger clade that also includes the S. jenningsi Malloch group. This more inclusive clade is defined chromosomally by a minimum of four fixed inversions, compared with the standard map for the subgenus Simulium. All four inversions are uniquely derived relative to the two selected outgroups, Simulium (Psilozia) vittatum Zetterstedt and Simulium (Boophthora) erythrocephalum (De Geer). The independent monophyly of the S. malyschevi and S. reptans groups, however, cannot be tested without study of additional group members. The problems illustrated by the taxonomic identity and phylogenetic placement of S. acrotrichum argue for an integrated approach to simuliid systematics, drawing from the character stores of morphology, cytology, and molecular biology.

The problem of sample size usually confronts the research worker in the initial stages of an investigation. Many short methods have been used for determining sample size such as extracting the square root of the number of boxes or taking a 10 percent sample. While these techniques are easy to use nevertheless they are not based upon a statistical evaluation of the experiment. Sample size in an experiment is often dictated by the amount of time, money and labor available but even under such conditions it is possible to evaluate the precision of the experiment when the number of replications is dictated by necessity.

Greenhouse and field trials were done to determine the potential of Heterorhabditis heliothidis (Khan, Brooks and Hirschmann) Poinar (NC19 strain), an undescribed Heterorhabditis sp. (NC447 strain), and Steinernema feltiae Filipjev (A32−6 strain) to control British Columbia populations of black vine weevil (Otiorhyncus sulcatus Fab.) and strawberry root weevil (O. ovatus L.). An outdoor application of H. heliothidis applied at rates of 500 and 5000 nematodes per litre of soil gave significantly better control of black vine weevil larvae on potted, lodgepole pine trees (Pinus contorta Dougl.) than did a diazinon drench. Under greenhouse conditions Heterorhabditis sp. NC447 was the most effective nematode of the three tested against O. ovatus on potted, Douglas-fir seedlings (Pseudotsuga menziesii (Mirb.) Franco) and S. feltiae the least effective, at all dose rates tested. A field trial using H. heliothidis against O. ovatus in a forest nursery did not provide a significant degree of weevil control. This lack of control is attributed to the average outdoor temperature (11 °C) during the treatment period, which was below the nematode’s optimum temperature range, and the higher-than-average rainfall.

Habrobracon lineatellae Fischer has been imported from Lebanon into California in the course of a project on the biological control of the peach twig borer, Anarsia lineatella (Zeller). The navel orangeworm, Paramyelois transitella (Walker), is used as a host to mass-culture this parasite. Its biology is similar to that of other species in the genus, for the female paralyzes the host before oviposition and the larvae develop ectoparasitically. Females begin to paralyze hosts 2 to 26 days after emergence, and oviposition is initiated 1 day after they begin this host paralyzation. The number of eggs per female varies from 32 to 954. A maximum of 12 larvae of H. lineatellae can develop on 1 larva of P. transitella. When virgin females are held for 4 days and then placed with sexually active males for the rest of their lives, the sex ratio of the progeny is 53% female. The adults do not host feed. Females fed honey–water live an average of 105 days (range 51 to 166 days).

One of the objects of the investigations on the European spruce sawfly, Gilpinia hercyniae (Htg.), in Eastern Canada was to discover and evaluate the factors of natural control affecting this introduced species in its new environment. Small mammal predators were found to be the most important factor affecting the sawfly cocoons, which were spun in the moss or litter of the forest floor (4, 5). These predators chewed large openings in the cocoons and pulled out the contents. Cocoons were also found with smaller openings made by the entry of insect predators, and occasionally such a cocoon was found with a larva of the family Elateridae partly inside (Fig. 1).

The faunal changes in the crown stratum of a newly established red pine plantation were observed during the first five years of growth. The crown faunae of three older stands planted in 1950, 1939, and 1929 were sampled throughout the growing seasons of four consecutive years by a technique employing pyrethrum insecticide.

The stands represent four stages in the development of a red pine community over a period of 35 years, and the presence, distribution, density, annual and seasonal fluctuations, species succession, and food relations of arthropod taxa are discussed.

Species colonizing trees in the establishment stage are largely replaced in the transition stage by a species-complex that persists throughout the succeeding monoculture and young-forest stages. Arthropod density in relation to crown size increases rapidly until the trees are about 15 years of age, and then declines. The pattern of seasonal abundance is dominated by a few species. The ratio between parasite–predator and prey species remains remarkably stable throughout the three older stages of the community.

Two Early Eocene hemerobiid species from the Okanagan Highland deposits of western North America are described: Wesmaelius mathewesisp. nov. (Quilchena, British Columbia, Canada) and Cretomerobius wehrisp. nov. (Republic, Washington, United States of America.). A poorly preserved specimen, possibly Hemerobiidae (Driftwood Canyon, British Columbia, Canada) is discussed. The systematic position of the genus Cretomerobius within the Hemerobiidae is unclear, but it appears to belong within (or possibly as the sister group to) the poorly differentiated Drepanacrinae–Megalominae–Drepanepteryginae grade of subfamilies. Wesmaelius mathewesi is the first fossil species to be assigned, although with some uncertainty, to this otherwise speciose and widely distributed extant genus. It also represents the oldest known material of the subfamily Hemerobiinae. Meso hemerobius jeholensis Ping is removed from the Hemerobiidae and treated as Neuroptera incertae sedis.