A review is given for the genus Obtusicauda Soliman in America north of Mexico. The subgenus Artemisaphis Knowlton and Roberts is restored to its original rank of genus. The species Obtusicauda essigi Soliman, O. jonesi (Gillette and Palmer), O. albicornus (Knowlton and Allen), and O. flavila (Knowlton and Allen) are considered to be synonyms of O. coweni (Hunter). The species O. cefsmithi (Knowlton and Allen) and O. zerohypsi (Knowlton and Allen) are considered to be synonyms of O. filifoliae (Gillette and Palmer). A key and an annotated list are given for the remaining six species of Obtusicauda.

Deutonymphs and adults of Oregonacarus rivulicolus gen.nov., sp.nov. are described, and distributional data are given for this and other species of Anisitsiellinae inhabiting seepage water habitats in western North America. A revised key to the nearctic genera of Anisitsiellinae and a brief discussion of their phylogenetic relationships are presented.

Adults of Cyclomomonia andrewi gen.nov., sp.nov. are described from interstitial habitats in small, cascading streams in western North America. The genus Cyclomomonia and the subfamily Cyclomomoniinae are proposed and diagnosed, based primarily on the distinctive, complex structure of the dorsal and ventral shields and the genital field. Possible relationships between Cyclomomonia and other Momoniidae are discussed, and a new key to the world genera and subgenera of the family is presented.

A mark–release–recapture study was conducted with dye-marked eastern subterranean termites, Reticulitermes flavipes (Kollar), at two sites in metropolitan Toronto. Interconnected termite galleries were found to extend up to 79 m and to cover areas of 266 and 1091 m2. Colony foraging populations at the two sites were estimated at 2.1 and 3.2 million termites. These foraging distances and population estimates exceed those reported for R. flavipes in other regions.

The sex pheromone components of the black army cutworm, Actebia fennica (Tauscher), were identified in abdomen-tip extracts from calling female moths. The primary pheromone component was (Z)-7-dodecenyl acetate. Although (Z)-11-tetradecenyl acetate was detectable only in trace quantities in the extracts, it was the major component in the best synthetic blend for attraction of male moths. The most effective synthetic blend was (Z)-7-dodecenyl acetate and (Z)-11-tetradecenyl acetate at a ratio of 1:20. No other component detected in the extracts increased trap capture of males when added to the two-component blend; however, (Z)-5-dodecenyl acetate, (Z)-7-dodecenol, and (Z)-9-tetradecenyl acetate reduced catches. This two-component blend will be useful for studying the habits of the adults and for population monitoring.

Micrempis anatolica Chillcott is considered a junior subjective synonym of M. bomboxynon Chillcott, based on re-examination of purported differences in the female terminalia given by Chillcott and Teskey (1983), as well as examination of a number of additional specimens collected from eastern North America. As a result of its new broader concept, M. bomboxynon is redescribed, a distribution map of the species is provided, and separation from other Nearctic species of Micrempis is discussed.

The spatial and frequency distributions of Douglas-fir cone moth, Barbara colfaxiana (Kearfott), eggs in Douglas-fir trees and stands were determined by dissecting 13 262 conelets collected from 81 trees in three sites and 2 years. There were no consistent trends in egg density associated with crown level or aspect. The frequency distribution of eggs per conelet fitted the negative binomial in three of five site-years but a common k for the negative binomial could not be calculated. Green’s index of aggregation suggested that the cone moth egg distribution was significantly aggregated in each site-year.

The optimal number of conelets per tree to sample was determined to be four in forest stands and three in seed orchards. The number of sample trees required for estimating mean egg density with 10% and 20% precision and 90% confidence was calculated for a range of mean egg densities using the method of Kuno. The sample sizes required to estimate a control threshold density of 0.6 eggs per conelet with 10% precision and 90% confidence were very large and would be impractical for operational use. Therefore, a sequential sampling plan was developed for use in seed orchards that would classify cone moth egg densities as either above or below a critical density at which 10% seed loss would be expected.

Analysis of 10 years of grasshopper survey data (1978–1987) indicated that grasshopper populations in fields can be reliably predicted from roadside survey counts. Direct estimation of grasshopper densities in crop fields is no longer required for summaries of infestation levels or forecasts. Spatial autocorrelation was significant and positive for both roadside and field counts. The coefficient of variation of the field counts was greater than that of the roadside counts in each of the last 10 years. Population density was summarized by crop type and sampling method for the last 10 years. Linear regressions fitted to the 1978–1984 grasshopper survey data were used to estimate field population density from crop type and roadside counts in 1985–1987. Maps of population density were generated from the predicted and observed field counts with SPANS, a microcomputer-based geographic information system. Large coefficients of association (73–79%) between the predicted and observed maps attested to the sufficiency of road-side counts as the basis for production of population density maps.

Two, 1400-ha blocks of rangeland in western South Dakota were treated aerially with malathion liquid spray or carbaryl – bran bait in early July 1986 to determine the immediate and 2nd-year impact of treatments on grasshopper populations. Total grasshopper populations were reduced by 92 and 47% in the malathion and carbaryl – bran bait treatment plots, respectively, within 48 h after treatment and remained at a low level throughout the summer. Populations did not change in the control plots. Populations of the two most abundant species, Ageneotettix deorum (Scudder) and Melanoplus sanguinipes (F.), declined by 65 and 87%, respectively, in the carbaryl – bran bait plots but populations of bran "rejectors" (predominantly Trachyrhachys kiowa [Thomas]) did not change.

Densities of the bran "acceptors" (Melanoplus spp., Phoetaliotes nebrascensis [Thomas], and A. deorum), as a group, did not change significantly in the control plots between the pre-treatment and July 1987 sampling dates. Densities within both sets of treatment plots were significantly lower in the 2nd year of the study than on the pre-treatment sampling date. Although 2nd-year populations of bran acceptors, as a group, did not increase to pre-treatment levels in the treated plots, populations of M. sanguinipes did increase to pre-treatment levels in both sets of treatment plots. Populations of bran rejectors generally remained low in treatment and control plots.

Analysis of covariance of the densities of 2nd-year populations of total grasshoppers and bran rejectors indicated that treatment had no significant effect on populations of these grasshoppers, but the covariable, pre-treatment density, was significantly correlated with 2nd-year densities. Densities of 2nd-year populations of bran acceptors were also significantly correlated with pre-treatment densities.

It was concluded that both the insecticidal spray and bait were effective in controlling most economically important species of rangeland grasshoppers. Although both treatments may have suppressed populations of bran acceptors, as a group, in the 2nd year of the study, neither suppressed populations of M. sanguinipes which increased to pre-treatment levels regardless of treatment. The effect of treatments on 2nd-year populations of bran rejectors could not be determined because populations of this group also declined in control plots.

Collections of larvae over 1 year in the River Clinton in the White Mountains of southern Québec indicated that Palaeodipteron walkeri Ide is bivoltine and that there are five larval instars. In April, larvae were in their fourth and fifth instars. Adults emerging in May and June gave rise to a summer generation in which most individuals emerged in August and September. The offspring of these adults, together with stragglers from the summer generation, formed an overwintering generation. Overwintering was completed in the larval stage, mainly the third and fourth instars. There was some growth in winter and development increased in the spring. Our data were compared with previously published observations; although no discrepancy occurred, our interpretation was different. Previous schemes proposed for the life cycle in this species were based on few specimens and lacked winter observations.

George Holland's superb monograph on the fleas of Canada, Alaska and Greenland was published as Memoir of the Entomological Society of Canada No. 130 on 11 March 1985 (not in 1984 as indicated on the spine of the monograph). This work was immediately adopted by those of us working with the northern North American flea fauna. Because of George's lengthy illness, he was unable to correct galley proofs to his usual high standards. Unfortunately, George Holland passed away later in 1985, before he was able to address corrections to the monograph. What follows is a compilation of the errors that we have detected since the monograph was published. We have made no attempt to reinterpret Holland's taxonomic or biogeographical concepts, nor in any way change the meaning of the text. We have included additional references that pertain to the relevant geographic areas, either where Holland did not refer to them in the text, or which appeared subsequent to completion of the manuscript, up to and including year of publication (1985). The authors thank Agriculture Canada for financial support in the publication of this manuscript.

Pristiphora harai sp.nov. collected on red spruce, Picea glehnii Masters, in Hokkaido is described, illustrated, and compared with P. ezomatsuvora Togashi.

Russian wheat aphid, Diuraphis noxia, was first detected in Canada in late July 1988 when a few were found on late-maturing spring cereals in southern Alberta near the International Boundary between Coutts and Aden. By the end of September, after dispersal or further immigration influx, it was widespread in Alberta south of Highway #3 and in southwestern Saskatchewan as far east as Swift Current. By mid-October more than 30% of the plants in many fields of winter wheat and fall rye in southern Alberta and up to 20% of plants in some fields of fall rye in southwestern Saskatchewan were infested. In November, Russian wheat aphid was also found on winter wheat in the Creston Valley of British Columbia.