Graham (1968) demonstrated that logs became attractive to ambrosia beetles after the sapwood was subjected to anaerobic conditions. Pursuing this lead, Cade et al. (1970) and Moeck (1970a, 1970b, 1971) extracted, analyzed, and bioassayed anaerobic products from western hemlock and Douglas-fir trees and ascertained that ethanol was the principal “primary attractant” to the ambrosia beetles, Gnathotrichus sulcatus (LeConte) and Trypodendron lineatum (Olivier), respectively. The demonstration that ethanol enhanced the response of the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, to its aggregation pheromones frontalin and seudenol (Pitrnan et al. 1975) suggested that ethanol could also be involved in the primary attraction of or host recognition by bark beetles. We report that the mountain pine beetle, Dendroctonus ponderosae Hopkins, is arrested to ethanol in a laboratorv olfactometer.

Since the writer's report on “The Subarctic Odonata of North America” was published, several collections have been received from localities included within the territory covered in that paper, which add materially to our knowledge of the dragonfly fauna of the Hudsonian Zone on this Continent. Most of these collections are from the Northwest Territories but a few are from northern Alberta and Newfoundland.

Our knowledge of the phylogenetic relationships of Diptera advanced through the 20th century at an unprecedented rate; the two crowning achievements of the century were Hennig's magnum opus – the Handbuch der Zoologie treatment of the order and Volume 3 of the Manual of Nearctic Diptera series, edited by McAlpine and Wood. The Manual is outstanding because of its scope and rigorous, consistent approach, treating the relationships of the entire order at family level using Hennigian argumentation. Synapomorphic characters from all life stages were identified using outgroup comparison and monophyletic taxa were established using synapomorphies mapped onto nodes. The Manual chapters energized a generation of students to publish rigorous, quantitative cladistic phylogenetic treatments of many dipteran groups. The chapters also acted as an authoritative scaffold for the development of dipteran molecular systematics in the 1990s. No other megadiverse insect order has had such an influential phylogenetic springboard into the 21st century.

The genus Serropalpus differs from other genera in the tribe Serropalpini in having an almost obliterated suture between the prosternum and the episternum, long slender antennae, and strongly serrate maxillary palpi which have a cultriform terminal segment. It is like Phloeotrya and Dircaea in having a short prosternum before the anterior coxal cavity.

The literature dealing with the methods by which the larvae and adults of tachinid parasites escape from sawfly cocoons indicates in certain cases that only circumstantial evidence is available concerning the formation of the exit hole in nature. Among these parasites a large number leave their hosts while the sawflies are in the larval stages. The larvae make their escape as mature maggots through a hole gnawed in the soft host integument. A few species, however, continue to develop within the host after the host cocoon has been formed. Some of these cut through the cocoon as mature larvae and later pupate in a suitable medium, while others form their puparial cases within the host cocoons, the adults later escaping from both the puparial cases and from the sawfly cocoons. The only escape mcchanism possessed by an adult tachinid fly consists ot the alternate expansion and contraction of the ptilinum against the surrounding wall. Since the cocoon is usually quite tough and leathery it is essential that some provision be made in advance to enable the adult to escape. This seemed to occur with adults of Phorocera hamata A. and W. which emerge from their puparia within the host cocoon and then escape from the cocoon proper, leaving a characteristic round cap which appears to have been cut (Fig. 1, C). The method of formation of this cap has been the subject of discussion by several authors.

On June 20, 1950, aphids were collected from grass on the Tantramar marshes at Middle Sackville, N.B. The aphids were causing serious damage and turning the grass brown. The writer was unable to place the aphid in a genus according to Hottes and Frison (193l), Gillette and Palmer (1931), or Baker (1923). However, according to Baker (1920) and Theobold (1929) the aphid would fall in the genus Atheroides Haliday, on the basis of the shape of the cauda. It differed from the descriptions by Laing (1920) and Baker (1920) of the genus Atheroides in that the cornicles were prominent. In February, 1955, several specimens of the aphid were sent to Mr. J. P. Doncaster, British Museum of Natural History, who (in litt.) determined the specimens as of Sipha agropyrella (H.R.L.). Dr. Hille Ris Lambers, Bennekom, Holland agreed (in litt.) with this determination.

A survey was recently undertaken by the author with Dr. V. P. Rao, Entomologist-in-charge, Indian Station, Commonwealth Institute of Biological Control, Bangalore, India, for natural enemies of Adelges spp. attacking silver fir (Abies spp.) and spruce (Picea spp.) in the North-West and Eastern Himalayas. In the course of this survey it was found that the coccinellids Coccinella septem-punctata L., C. septempunctata L. var. divaricata Oliv. and C. septempunctata L. var. confusa Wied, were three of the most common predators of Adelges spp. in both these areas. With a view to sending laboratory-reared material to Canada for trial against Adelges piceae Ratz., which is a serious pest there, large numbers of these Coccinellids were collected in the fir and spruce forests to provide breeding material.

To determine resistance of Brassicaceae field crops to Contarinia Róndani (Diptera: Cecidomyiidae) midge complex (Contarinia nasturtii Kieffer and Contarinia undescribed species), field trials of two different host assemblages were undertaken near Melfort, Saskatchewan, Canada in 2014 and repeated in 2015. In both years the first midge adults appeared in early July, when most plants were starting to flower, and a second generation occurred in mid-August, past the period of crop susceptibility. In a trial studying 18 lines of six brassicaceous species, the lowest probability of midge injury was found on Camelina sativa (Linnaeus) Crantz lines in both years. No differences were found in the probability of midge injury among any of the 13 Brassica Linnaeus species lines tested, including commercial glyphosate-resistant and glufosinate-resistant Brassica napus Linnaeus canola lines, Ethiopian mustard (Brassica carinata Braun), brown or oriental mustard (Brassica juncea (Linnaeus) Czernajew), or Polish canola (Brassica rapa Linnaeus) lines. Probability of midge injury on Sinapis alba Linnaeus yellow mustard lines reached levels between those on Camelina sativa lines and those on Brassica lines. A second trial examining 14 current commercial glyphosate-resistant Brassica napus canola cultivars found no differences in susceptibility to midge feeding among any cultivars tested. More plants were damaged in 2015 in both studies, and damage reached maximum levels earlier in 2015 than in 2014.

Leafy spurge (Euphorbia × pseudovirgata [Schur]) is an herbaceous perennial and serious weed of European origin that has been accidently introduced into North America. The European anthomyiid flies Pegomya curticornis (Stein) and Pegomya euphorbiae (Kieffer) are found on several spurge species in Europe and also attack leafy spurge. The two flies induce identical galls on the subterranean stems of their host plants, and the shoots wilt and die. Eggs are laid on the shoot tip, and the larvae bore into the stem by eating pith which is later replaced by callus. This is a rare example of an insect with both boring and gall-inducing feeding strategies. Galls are induced when larvae feed on the ring of vascular tissue. There is no proliferation of nutritive cells but instead thick layers of gall parenchyma are produced. The vascular connections are broken at the gall level and concentric vascular bundles appear in the cortical and gall parenchyma. After pupation an inner periderm differentiates around the chamber surface.

Diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), was first recorded in North America from Europe about 150 years ago and can be a significant pest of canola in Western Canada. Because parasitism of P. xylostella in Canada is generally low, the introduction of one or more additional exotic parasitoids from Europe is being considered to increase the suppression of P. xylostella populations. Life table studies to determine the impact of parasitoids on diamondback moth populations in Europe were conducted in northwestern Switzerland in 2014–2016. Net reproductive rates were found to be less than one in seven out of eight life tables, suggesting that P. xylostella populations in Switzerland are mostly driven by immigration and recolonisation. In total, seven primary parasitoid species and one hyperparasitoid were associated with diamondback moth. Pupal parasitism by D. collaris reached up to 30%, but because generational mortality was mainly driven by abiotic mortality factors and predation of larvae, the overall contribution of pupal parasitism was low (< 6%). In regions of Canada, where P. xylostella may have increasing populations and low larval mortality, the addition of D. collaris may be a promising approach. Life table studies across Canada are necessary to determine the need for such intervention.

Bald eagles (Haliaeetus leucocephalus (Linnaeus); Accipitriformes: Accipitridae) from 92 locations in Manitoba were examined for chewing lice (Phthiraptera: Amblycera and Ischnocera) from 1992 to 2017. Bald eagles were salvaged from rehabilitation hospitals and were examined using two methods, dry-ruffling (n = 107) and washing (n = 40). We collected 39 066 bald eagle lice of four genera and six species: Colpocephalum flavescens (De Haan), C. napiforme (Rudow), C. turbinatum (Denny) (Phthiraptera: Menoponidae) (total for all Colpocephalum species = 18 082), Craspedorrhynchus halieti (Osborn) (Phthiraptera: Philopteridae) (n = 49), Degeeriella discocephalus (Burmeister) (Phthiraptera: Philopteridae) (n = 20 912), and Kurodaia fulvofasciata (Piaget) (Phthiraptera: Menoponidae) (n = 23). Quantitative data were collected on all genera with the comparison of washed to dry-ruffled. Colpocephalum flavescens and D. discocephalus dominated the louse populations, with similar prevalence and mean intensity. Both genera had sex ratios near 1.0, and similar nymph-to-female ratios near 3:1. The dry-ruffling method was relatively inefficient, collecting 11% as many lice as the washing method. Total prevalence for dry-ruffled birds was 63%; total mean intensity was 103.5, but for washed birds, the prevalence was 93% with a mean intensity of 861.1. No Laemobothrion vulturis (Fabricius) (Phthiraptera: Laemobothriidae) were found.

Aphidius ervi Haliday (Hymenoptera: Braconidae) is a major natural enemy of several agricultural pests in North America. Yet little is known about its overwintering strategy, especially concerning the plastic response to photoperiod and temperature that induce diapause. Information on parasitoid overwintering patterns is of great importance if we aim to predict their phenology and better inform pest outbreak control. Moreover, there is increasing evidence of plastic and genetic changes in overwintering strategies in insect from temperate areas following climate change. We set up a laboratory approach to better understand the factors acting on diapause induction in A. ervi. We studied the diapause incidence in a population from Québec, Canada, using the combination of two temperatures (14 °C and 20 °C) and three photoperiod treatments (10:14, 12:12, 14:10 [light:dark] hours). We found an effect of both factors on diapause incidence; A. ervi expressed close to 95% of diapause at the most fall-like conditions (14 °C, 10:14 [light:dark] hours) and almost no diapause (3.5%) at the most summer-like conditions tested (20 °C, 14:10 [light:dark] hours). This parasitoid species does have the potential to enter diapause in Québec before lethal frosts, despite a recent introduction from France (1960s), where mild winter occurs compared with Québec.

The Poweshiek skipperling (Oarisma poweshiek) is endemic to the tall grass prairie in North America and is now critically endangered globally. Existing populations are scattered among tall grass prairie remnants. However, the host food plants eaten by Poweshiek skipperling larvae, the vegetative and microclimatic descriptions of immature and adult microhabitats, and O. poweshiek behaviour in Manitoba are unknown. We followed Poweshiek skipperling adults in their natural habitat to locate microhabitats where eggs were laid and to observe larval foraging behaviour and development. We measured vegetative, structural, and microclimatic characteristics of microhabitats used by immatures and documented the host species larvae consumed, their general behaviour (on plants; movement within microhabitats), and their developmental schedules. Larvae ate Andropogon gerardi, Muhlenbergia richardsonis, Sporobolus heterolepis, and Schizachyrium scoparium (all Poaceae) in natural tall grass prairie. Larvae appeared to navigate microhabitats to locate host food plants, alternating between shoots of various species throughout their development. Microhabitats seemed to be more open, with drier microclimates, than areas where eggs were not laid. This improved understanding of larval feeding patterns, adult behaviours, and microhabitat attributes may help local grassland stewards and researchers reduce the list of possible causes of decline and identify potential solutions to recover the Poweshiek skipperling.

Mr. Scudder, in his “Butterflies,” p. 136, says of this species: It is the longest lived of our butterflies. It leaves its winter quarters later in the season than other hibernating butterflies, and continues upon the wing until July and August, laying eggs all the time, so that the insect may be found in all its earlier stages most of the summer.

The excellent monographic studies of Brennan (1935) and Stone (1938) on Nearctic Tabanidae and the even more recent catalog of Philip (1947) has placed the study of this group on a firm foundation. The student of this family rarely suffers from a dearth of material since the abundance of individuals of many species, their ease of preservation and their economic importance lead to the collection of long series. As these series accumulate, it sometimes is found that certain species exceed the limits of variation conceded that species, and in other cases what appear to be new forms, may be separated.

High volume sprays of azinphosmethyl, chlorpyrifos, fenvalerate, permethrin, and phosmet in various concentrations and formulations were simulated on loblolly pine (Pinus taeda L.) foliage in a pine seed orchard in northern Georgia. Persistence of these insecticides under field conditions was determined by weekly bioassays with adult leaffooted pine seed bugs [Leptoglossus corculus (Say)] and gas–liquid chromatography. Fenvalerate was the most persistent insecticide tested. In the first experiment, 0.2% AI fenvalerate caused virtually 100% seed bug mortality in bioassays through the 4th week after treatment, whereas mortality from azinphosmethyl dropped to ca. 14%. By the 6th week, mortality in the fenvalerate treatment was still 91%, even after 10.5 cm of rain. The permethrin treatments persisted for 2 weeks, then mortality declined below 40% at 3 weeks. In the second experiment, fenvalerate at 0.15% AI and 0.075% AI caused 95 and 90% mortality, respectively, after 3 weeks and 16 cm of rain, and the toxicity of the 0.038% and the 0.019% AI fenvalerate treatments lasted only 2 weeks with 12 cm rain. Permethrin in Ambush® EC at 0.2% AI had initial residues of about 150 ppm and caused ca. 84% mortality for 2 weeks with 12 cm rain. Azinphosmethyl WP at 0.2% AI had initial residues of ca. 104 ppm and persisted for 1 week. Seed bug mortality from phosmet at 0.4% AI diminished quickly after 1 week in the field.

The sex pheromone of the peach twig borer, Anarsia lineatella (Zeller), was identified 30 years ago but the communication biology of this species has hardly been studied. In laboratory experiments, female moths kept at a photoperiod of 16L:8D (20 ± 2 °C, 70% ± 5% relative humidity) emitted pheromone before, during, and after sunrise (0400–0600 Pacific standard time), whereas pheromone was present in pheromone glands at similar quantities throughout the 24 h recording period. These data suggest that pheromone production and emission are not closely linked. In field experiments during July 2001 near Livingston, California (CA), and during June 2002 near Keremeos, British Columbia (BC), males were attracted to traps baited with synthetic sex pheromone (CA) or conspecific females (BC) only between 0300 and 0600 (Pacific standard time), suggesting overlap between periods of pheromone emission by females and attraction response by males. Groups of females in the presence of conspecific males, which were physically separated from females, emitted less sex pheromone than groups of females in the absence of males, suggesting that males communicate their presence to females and females change their behaviour in response.