The Ceratozetidae of arctic western North America, represented by 12 species in 9 genera, are discussed. A new genus, Cyrtozetes, and species, Cyrtozetes denaliensis, are proposed, and Trichoribates copperminensis Hammer, T. polaris Hammer, Svalbardia paludicola Thor, Iugoribates gracilis Sellnick, Diapterobates notatus (Thorell) both adults and immatures, D. variabilis Hammer, Sphaerozetes arcticus Hammer, Fuscozetes sellnicki Hammer, Melanozetes longisetosus Hammer, and Ceratozetes spitsbergensis Thor and C. parvulus Sellnick are redescribed. Immatures of T. polaris, S. paludicola, F. sellnicki, and M. longisetosus are described. Distribution records of Ceratozetes gracilis (Michael) in the western North American arctic are listed. The new combination, Cyrtozetes shiranensis (Aoki and Fujikawa), is proposed.

Observations on the biology of Trybliographa rapae (Westw.) were made as part of a general study, in Canada and Europe, of the biotic factors acting against the maggots of Hylemya brassicae (Bouché), H. floralis (Fall.) [H. crucifera Huck.], and H. cilicrura (Rond.) that attack cruciferous crops. During the study many thousands of host insects from both Canada and Europe were examined and large numbers of both hosts and parasites were reared in the laboratory.

Sixteen genera are recognized in the Clinocerinae (Diptera: Empididae): Dipsomyia Bezzi, Proagomyia Collin, Asymphyloptera Collin, Proclinopyga Melander, Rhyacodromia Saigusa, Trichoclinocera Collin, Clinocera Meigen, Oreothalia Melander, Roederiodes Coquillett, Clinocerella Engel, new status, Hypenella Collin, Kowarzia Mik, Dolichocephala Macquart, Phaeobalia Mik, Bergenstammia Mik, and Wiedemannia Zetterstedt. The subgenera of Clinocera are no longer recognized and the genus is divided into six tentative informal species groups. The following new generic synonyms are proposed: Hydrodromia Macquart = Clinocera; Archiclinocera Frey and Hypoclinocera Frey = Kowarzia; Lamposoma Becker, Fur Garrett Jones, and Obstinocephala Garrett Jones = Dolichocephala. A key to genera is provided for the identification of adult specimens of Clinocerinae, all genera are described, several lectotypes are designated, and male and female terminalia are illustrated. A world list of species is included for each genus, identifying new combinations. Cladistic relationships of the genera of the Clinocerinae are presented.

Zanclotus Wilder is transferred from the Clinocerinae to the Oreogetoninae. Dryodromia Rondani, also formerly in Clinocerinae, is considered to be most closely related to Hesperempis Melander, both of which are hypothesized to share apomorphies with the Empidinae + Hemerodromiinae. The genera Boreodromia Coquillett, Ceratempis Melander, Ephydrempis Saigusa, Niphogenia Melander, Sabroskyella Wilder, and Trichopeza Rondani also are removed from the Clinocerinae and transferred to the subfamily Trichopezinae, new status. In addition, Apalocnemis Philippi, Gloma Meigen, Hyperperacera Collin (all formerly in Oreogetoninae) and Heleodromia Haliday (formerly in Hemerodromiinae) are transferred to the Trichopezinae. Heterophlebus Philippi (formerly in Oreogetoninae) and Rubistella Garrett Jones (formerly in Brachystomatinae) are removed from synonymy and also transferred to the Trichopezinae. This subfamily is described, and the phylogenetic relationships and.geographic distribution of the included genera are discussed. The Trichopezinae is considered most closely related to the Brachystomatinae (exclusive of Homalocnemis Philippi) and Ceratomerinae. These three subfamilies are hypothesized to represent the sister group to the Microphorinae + Dolichopodidae.

Microplitis mediator (Haliday) is being considered for introduction into Saskatchewan to augment the biological control of the bertha armyworm, Mamestra configurata Walker. It was reared in the laboratory on larvae of the bertha armyworm. Notes on the life history and descriptions of the egg and three larval stages are given.

We examined the effect of forest structure and climate on large-scale and long-term patterns of outbreaks of forest tent caterpillar, Malacosoma disstria Hbn., across central Ontario. This was done using previously published data on outbreak duration and forest heterogeneity, combined with high-resolution climatic data simulated by the recently developed Ontario Climate Model. Our analysis, which eliminates some of the spatially confounding effects of forest structure and climate, suggests that both the predicted long-term temperature minimum for the coldest month and the predicted growing degree-days in the first 6 weeks of the growing season are important determinants of outbreak duration, with colder weather being associated with shorter outbreaks. Forest heterogeneity accounts for more variation in outbreak duration than either of the climatic variables.

Escherich (7) was the first to report a polyhedral virus disease affecting the European pine sawfly, Neodiprion sertifer (Geoffr.). Later Forsslund (8) observed that populations of this insect in Sweden were controlled by a virus disease. In 1948, H. S. Hanson. Entomologist of the Forestry Commission, England, observed mortality among N. sertifer in England which was due to a polyhedral virus disease (10). In 1949 virus-killed larvae collected in Sweden by Forsslund, were sent to the Laboratory of Insect Pathology, Sault Ste. Marie by G. R. Wyatt of this laboratory and the virus from these insects was propagated and used in the biological control of N. sertifer in southern Ontario (3, 5). This paper describes some aspects of the laboratory studies of the disease, namely: the infection process in cells susceptible to the virus, incubation period of the disease, and the isolation and electron microscope study of the causal agent.

The house cricket, Acheta domesticus (L.) (Gryllidae, Orthoptera), is a cosmopolitan and easily available insect, and is most suitable as a test animal for physiological research, as has been pointed out by Stone (1953). However, in spite of the long familiarity of entonlologists with this insect it has received very little attention in the literature, no doubt because it has never been of economic importance in Europe or North America. Such quantitative observations on its development as do exist are rather fragmentary (Kemper, 1937; Stone, 1953; Busvine, 1955). The present article describes, in a somewhat more precise way, the rate of development of the nymph of the house cricket at various temperatures and the number and duration of the nymphal stadia, as well as a satisfactory method of rearing the insect and observations on its fecundity.

Phenology, fecundity, development, and mortality were studied for co-occurring, declining populations of Dendroctonus ponderosae Hopkins in limber pine and lodgepole pine at two sites in the Porcupine Hills of southwestern Alberta in 1985–1986. Beetles reared in lodgepole pine emerged and attacked new hosts 7–8 days earlier than those in limber pine in 1985. Beetles were able to utilize over two-thirds of the length of each limber pine bole but only about one-third of the length of each lodgepole pine bole. Also, beetles infesting limber pine had significantly higher fecundity, produced more eggs per centimetre of gallery length, and their progeny developed faster and survived better than beetles infesting lodgepole pine. There was no apparent phenological or other barrier that might inhibit gene flow between D. ponderosae populations in limber pine and lodgepole pine. In the area studied, limber pine was a better host for D. ponderosae reproduction, development, and survival than was lodgepole pine. Thus, beetle populations may be able to increase much more quickly in limber pine, arguing for regular monitoring of these populations.

This review of the tribe Xyleborini (Coleoptera: Scolytidae) includes two genera, Xyleborus Eichhoff, with 17 species, and Xylosandrus Reitter, containing 3 species. All species are described and most are illustrated. Keys for the separation of the genera and species are provided. Distributional and biological data are given. New combinations are: Xyleborus obliquus (Leconte) (= Pityophthorus obliquus Leconte); X. lecontei (Hopkins) (= Ambrosiodmus lecontei Hopkins), and X. sayi (Hopkins) (= Anisandrus sayi Hopkins). New synonymies are: Xyleborus obliquus (Leconte) (= Ambrosiodmus linderae Hopkins); X. obesus Leconte (= Anisandrus populi Swaine); X. ferrugineus (Fabricius) (= X. retusicollis Zimmerman and X. soltaui Hopkins); X. xylographus (Say) (= X. inermis Eichhoff and X. planicollis Zimmerman); X. volvulus (Fabricius) (= X. schwarzi Hopkins and X. rileyi Hopkins), and X. howardi Hopkins (= X. fitchi Hopkins). A Japanese species, X. rubricollis Eichhoff, is reported from the United States for the first time. A neotype is designated for X. xylographus (Say).

The fecundity of the migratory grasshopper, Melanoplus bilituratus (Wlk.), when reared under a variety of conditions, has been reported by a number of authors. In the laboratory, Barnes (1955), rearing cultures of the subspecies found in Arizona on five separate foods, obtained an average production of 8.8 egg-pods per female from those fed the most favourable diet; Parker (1930) reported an average production of 8.8 egg-pods per female from Montana specimens reared on a mixed diet; one of these females laid 15 egg-pods. Under field conditions, Pfadt (1949) in Wyoming and Smith et al. (1952) in Manitoba reared this species on a variety of food plants and reported that the greatest numbers of egg-pods per female resulting from use of the most favourable food plants were 9.8 and about 6 egg-pods, respectively.

In Quebec commercial apple orchards, spider populations are shown to have been depressed numerically by current pest management practices. Hunting species appeared to be more sensitive to insecticides than web-building species. There were large differences in spider distribution among orchards and years, although some consistent patterns were observed. Specimens from the following families were captured: Theridiidae, Linyphiidae, Lycosidae, Araneidae, Erigonidae, Clubionidae, Tetragnathidae, Dictynidae, Salticidae, Philodromidae, and Thomisidae. In orchards treated only for scab control or with only a single insecticide application for apple maggot control, spiders attained their maximal numbers in August. With two treatments for apple maggot control, spiders attained their maximal numbers towards the end of September.

Bees (Hymenoptera: Apoidea, Apiformes) are taxonomically and ecologically diverse, with a wide range of social complexity, nesting preferences, floral associations, and biogeographic restrictions. A Canadian bee checklist, greatly assisted by the gene-assisted approach of DNA barcoding, is nearing completion. Previous evaluation of bee diversity in Canada, assisted by DNA barcoding, was restricted to Nova Scotia, which contains about 25% of the bee species in the country. Here, we summarise efforts to date to build a comprehensive DNA barcode library supporting bee taxonomic studies in Canada, consisting of more than 12 500 barcode-compliant sequences yielding 811 distinct barcode index numbers (BINs). This appears to represent ~95% of the 856 bee species presently recorded from Canada, but comparison with known morphological species in each genus shows that some genera are still under-sampled or may contain cryptic taxa, with much taxonomic work still to be done on bees in Canada. This is particularly true within the taxonomically difficult genera Andrena Fabricius (Andrenidae), Hylaeus Fabricius (Colletidae), Melissodes Latreille (Apidae), Nomada Scopoli (Apidae), Osmia Panzer (Megachilidae), and Sphecodes Latreille (Halictidae). DNA analysis will likely be a key asset in resolving bee taxonomic issues in Canada in the future, and to date has even assisted studies of well-known bee taxa. Here we present summaries of our results, and discuss the use of DNA barcoding to assist future taxonomic work, faunal lists, and ecological studies.

Adults of B. cephi emerged at the same time as the adults of their host, the wheat stem sawfly, and started to oviposit about mid-July. The second generation started to emerge between August 5 and 15. This generation, which was complete in some years, was apparently only partial in years in which adults of the first generation continued to oviposit late in the season. In most cases the larvae of Bracon that were present at harvest time were from eggs laid after August 1.

Most of the overwintering B. cephi were located in the lower internodes of the sawfly-infested wheat stems. Although B. cephi attacked some sawfly larvae in their stubs most sawflies escaped parasitism once they had cut their host stems.

High host densities per stem in hollow-stemmed wheats were detrimental to Bracon during the early part of the season as the unparasitized sawfly larvae in stems containing B. cephi destroyed the parasite larvae.

The sawfly-susceptible wheats were more suitable than the resistant for parasitism. Generally, differences in parasitism between wheats and between barleys were caused by differences in length of survival of the sawfly larvae in the different host plants; longer survival led to higher parasitism.

The fluctuations in amounts of parasitism mainly depended on the synchronization of development between B. cephi and the sawfly. Parasitism increased when the sawfly larvae cut their host stems sufficiently late to allow establishment by the second generation of B. cephi and decreased when the sawfly cut too early for parasitism by the second generation. The date of ripening of the host plant governs the date of cutting by the sawfly; hence, the amount of parasitism is influenced by the levels of soil moisture and temperature during the growing season, by differences in rate of development of various plant hosts, and by the date of seeding. Low levels of parasitism resulted from early ripening of the sawfly host plants in two consecutive years, whereas a moderately high level occurred even though the weather of the current year was conducive to early ripening, provided that the wheat in the preceding year had ripened late. It appears that moderate to high levels of parasitism required that the crop ripen late in at least one year out of two.

The influence of nitrogen levels in foliage of white-fir, Abies concolor, and Douglas-fir, Pseudotsuga menziesii, seedlings on various biological characteristics of the western spruce budworm, Choristoneura occidentalis Freeman, was studied. Seedlings were grown under greenhouse conditions and provided with nutrient solutions to maintain five foliar nitrogen levels ranging from 1.29 to 4.42% dry weight for white fir and 1.43 to 3.94% for Douglas fir. Larvae confined to treated seedlings were monitored through the next generation. Larval mortality was higher, and development time longer, at both upper and lower extremes of foliar nitrogen than at mid-level. Mean pupal weight was significantly greater for larvae reared on white fir with the mid-range foliar-nitrogen level. Mean number, and weight, of eggs laid were highest when larvae fed on foliage from the mid-range nitrogen level. Total number of larvae produced was lowest at the high and low extremes of foliar nitrogen levels.

The life history of Plutella xylostella (L.) was studied in plantings of Brussels sprouts at Cambridge, Ontario in 1977 and 1978. Adults were monitored by using sticky traps constructed of bristol board; eggs, larvae, and pupae were monitored by sampling plants. In both years in the spring, some of the first eggs were found before adults were caught in the traps. The trap collections indicated four periods of adult flight each year. During the last period of flight in 1977 eggs were laid; however, the fifth generation was not completed. Day-degree analyses of the populations indicated that 293 day-degrees (C) above a threshold temperature (7.3°C) were required to complete one generation. Using day-degree accumulations it was possible to predict accurately the periods when various stages of the pest were dominant even though there was considerable overlap of various stages in the field.

The predictions of three published models of temperature-dependent egg hatch of the European strain of the gypsy moth, Lymantria dispar L., were compared with observed hatch rates of caged egg masses in Victoria, British Columbia, Canada. Two of the three models gave a good fit to observations. Both of these models considered explicitly the period between oviposition in the summer of one year and hatch of neonates the following spring. When combined with models for temperature-dependent development of larvae and pupae, and adult longevity, the seasonal life history of an entire generation of gypsy moth could be simulated. These composite models predict the seasonal occurrence of all life stages of the insect. The simulated flight period of adult male gypsy moth on Vancouver Island in 1998 compared favourably with observed captures in pheromone traps. A series of gypsy moth generations was simulated using daily temperature inputs reconstructed from climatic normals (period 1961–1990) at various locations on the south coast and southern interior of British Columbia where gypsy moth has been frequently introduced but is not established. These simulations provided estimates of the probability of a persistent population resulting from a predicted stable seasonality of the gypsy moth. The highest probabilities of persistence were in coastal areas along the Strait of Georgia between Vancouver Island and the continental mainland and in southern interior valleys below approximately 500-m elevation (above sea level). Outside these regions, normal climatic profiles resulted in an unstable seasonality for gypsy moth with increasingly late oviposition dates, and subsequent problems in synchronizing initiation and completion of winter diapause with appropriate ambient conditions. The phenology models discussed here can be and were used as decision-support tools either to improve the efficiency of pest management operations (sampling, pesticide applications) or to make better decisions concerning the need for eradication of the gypsy moth in novel environments.

Two things make it difficult to write an account of Canada in relation to insect life: the vast size and varied nature of the country and the relatively small amount of work that has been done on its insects. Those familiar with the intensely worked biota of Western Europe or even of many parts of the United States will find this description meagre indeed. In general, Canadian environments are known better than the insects that inhabit them. In only a few orders of insects is our knowledge even of species taxonomy reasonably adequate; for all orders our knowledge of geographical distribution in Canada is sketchy or fragmentary and our knowledge of ecological relations almost non-existent. Serious collecting and study of insects has been carried out in only a few centres. The National Collection itself has been developed actively only since 1919, and on a large scale only in the last few years. There is no close network of amateur and professional workers such as exists in better-studied countries. What I have tried to do, therefore, is to give a brief geographic account of the main environmental factors as seen by an entomologist, to give a short outline of the possible history of the fauna, to give examples of the main distributional types, and to provide a tentative classification of entomological regions, with notes on some characteristic insects of each. The main feature that will undoubtedly be impressed on the reader, as it has been impressed on me, is our ignorance and the need for further investigation of the insect fauna.

Two bumble bee observation hive designs are described. Both have a sloping floor to support peripheral brood clumps. One is temperature controlled, using insulated resistance wire as an internal heat source. The other is moulded from a concrete mixture consisting of horticultural Perlite, cement, and plaster of Paris. Techniques for the sanitation, feeding, and handling of laboratory colonies are described.

An outbreak of the forest tent caterpillar began in northern Minnesota in 1964 and ended abruptly in 1972. During 1968–71 when egg densities ranged from 1 to 9 million per acre, caterpillars caused virtually complete tree defoliation in all study plots. As a result, tree stem densities and basal areas were reduced per plot by 41 and 27%, respectively. Tree mortality was more severe on plots having higher water tables. Graphical and components of variance analyses both showed that: (1) variations in annual egg densities were due mostly to variations in survival during the egg to 30-day larval stage (SI) and secondly to variations in survival during the 30-day larval to adult stage (S2), (2) S2 tended to change in the opposite direction from S1, (3) the net result was a tendency to produce a constant amount of eggs per unit area. Variations in S1 were due primarily to pharate larval mortality and mortality of larvae 2–3 weeks after hatch while variations in S2 were due mainly to unmeasured mortality factors such as starvation, disease, dispersal, etc. Survival during the egg stage (SE) and fecundity (F) varied significantly by years, but not by plots and both were apparently related to weather conditions. Plots of two simultaneous equations were presented to demonstrate the nature of population change in relation to the densities of eggs and 30-day larvae per acre.