Field tests were continued during 1970, 1971, and 1972 in southwestern Ontario to evaluate experimental and registered insecticides for control of Euxoa messoria (Harris) larvae on tobacco. Insecticides were applied before planting as broadcast applications to the rye cover crop or to the soil.

Of 10 chemicals tested, chlorpyrifos, leptophos, and N-2596 (S-(p-chlorophenyl O-ethyl ethyl-phosphonodithioate) gave the most consistent control, and Biothion® (O,O′-thiodi-p-phenylene O,O,O′,O′-tetramethyl phosphorothioate) and methoxychlor gave variable control. Fensulfothion was slightly phytotoxic, and trichlorfon and Mobam® (benzo [b] thien-4-yl methylcarbamate) were ineffective in the present study. Supracide® (O,O-dimethyl phosphorodithioate S-ester with 4-(mercaptomethyl)-2-methoxy-Δ2-1,3,4-thiodiazolin-5-one) and Orthene® (O,S-dimethyl N-acetyl phosphoramidothioate) showed promise for control of E. messoria larvae.

Levels of reducing sugars and total alkaloids in the cured leaves were unaffected by treatment, indicating that these insecticides had no effect on tobacco quality.

The premises for biochemical systematics are outlined, including the demonstration of colinearity between polypeptides and the nucleotide sequence of the gene, and subsequent comparative studies based on amino acid sequencing of proteins. Distinct differences in the stability in the amino acid sequences among various proteins demands that the systematist select those most appropriate to the taxonomic problem to be resolved. As sequencing is a difficult and time consuming task, an alternative analytical means of obtaining objective data by which taxa may be phenetically compared is proposed. Electrophoretic studies on the enzyme GDH from cockroaches and bumble bees are outlined and the use of the data in superspecific classifications is documented.

The question of whether the evolutionary origin of the parasitic bumble bees (Psithyrus Lep.) was monophyletic or polyphyletic has not been convincingly resolved by conventional systematics. In this study numerical taxonomic (NT) analysis was applied to data on wing venation from a set of 13 species of Psithyrus and 60 species of non-parasitic bumble bees (Bombus Latr.), representing 16 of the subgeneric divisions recognized by Richards. The resultant cluster analysis gave an almost perfect grouping of the constituent Bombus species into their ’correct’ subgenera. This was taken as evidence that the NT procedure had yielded discriminant criteria of evolutionary significance. Since the same criteria also produced a single grouping of the Psithyrus species, the results support a monophyletic origin for Psithyrus.

Parasitism by Pollenia rudis (Fabr.) larvae on earthworms in the field was found only in Allolobophora chlorotica (Sav.) and Eisenia rosea (Sav.). Other species of worms were infected in the laboratory. Slime and coelomic fluid, from all species of worms tested, induced penetration behaviour. Penetration occurs mainly on the dorsal surface of the worm, and less frequently towards either end. Larvae repenetrated after leaving the original penetration site. Autonomy by the host of the parasitized segments was observed in E. rosea. Possible reasons for the restricted natural host range are discussed.

Males of the fruittree leafroller, Archips argyrospilus (Walker), were attracted to traps containing either virgin females or cis-11-tetradecenyl acetate (cis-11-TDA) combined with dodecyl acetate. In two of three field tests traps containing virgin females captured significantly more males than the synthetic lure. Trap captures indicated that the ratio of cis-11-TDA to dodecyl acetate influenced the attractiveness of the mixture, but that increased amounts had no significant effect.

The morphological differences in the larva and the adult of Tetropium parvulum Casey and T. cinnamopterum Kirby are reported. Diagnostic characters are the urogomphi of the larva. The shape of the eye, scutellum, and genitalic structures and the number of punctures on the pronotum distinguish the adult. The genitalia are also compared with a third species, T. velutinum. Larvae of T. cinnamopterum have been recorded from a number of conifers, while T. parvulum larvae have only been recorded from spruce.

A lectotype is designated for T. cinnamopterum. Examination of type specimens confirmed that T. alaskanum Fall is a synonym of T. parvulum and that T. schwarzianum Casey and T. parallelum are close to T. cinnamopterum. A key is given to distinguish T. parvulum from T. cinnamopterum.

The larval parasite complex of Ips paraconfusus Lanier is found to differ in Pinus ponderosa and Pinus lambertiana within the same local area. Ips paraconfusus was attacked by fewer species of parasites in ponderosa pine and the rate of parasitization was generally less in that tree species. Greater parasitization in sugar pine was not entirely accounted for by the additional parasite species, but also reflected greater efficacy by those species common to both trees. Evidence indicates that greater bark thickness in ponderosa pine at comparable diameters may have been responsible for the higher parasitization by the shared parasite species.

A significant negative regression of parasitization with diameter was found in sugar pine, but not in ponderosa pine. Most, if not all, of this regression is attributed to a single species, Rhopalicus pulchripennis, whose searching appears to be confined to the smooth, softer bark of the crown.

The four larval instars and the pupa of Ptychoptera lenis lenis Osten Sacken are described. Instars 2 to 4 are very similar morphologically but instar 1 is markedly different. Both a pharate pupal and a pharate adult stage were observed. Larvae are found in stagnant marginal areas of ponds where water depth does not exceed 4 cm and where benthic deposits of plant detritus exceed 8 cm. Fourth instar larvae, under experimental conditions, survived up to 45 days without contact with atmospheric oxygen but development was arrested. P. lenis has a 1 year life cycle with an extended adult emergence season from late May to the end of July.

A numerical taxonomic analysis was performed using eight exemplars of the orthopteroids. Two suites of attributes were used in a non-weighted dissimilarities analysis. The same suites of attributes were analyzed for a similarity index with dendrograms based on the shortest connection network of Prim. The Tettigoniidae and Gryllidae are in agreement with current systematic placement within the Ensifera. The Caelifera diverge early from ancestral stem lines and suggest a greater separation from the Ensifera within the Orthoptera than generally accepted for their systematic position. The dendrograms suggest that the Blattaria and Mantodea show a relationship closer than the present subordinal rank permits. In the dendrograms the Grylloblattodea and Dermaptera form a remote complex from the other orthopteroids and each qualifies as a separate order. Modern classification of the orthopteroids considers the Dictyoptera, Dermaptera, Orthoptera, and Phasmida as orders. My analysis elevates the Grylloblattidae to the ordinal level as Grylloblattodea.

A 10,000 acre stand of mature balsam fir, in Temiscouata County, Quebec, which had a spruce budworm population of about 21 larvae/18 in. branch-tip was sprayed with a Bacillus thuringiensis + chitinase formulation. Aerial spraying was carried out by three TBM aircraft between 4 and 7 June 1972, when insect development was at the peak of the third instar. Where the quantity of B. thuringiensis colonies per square centimeter was higher than 77 and spray deposit higher than 0.4 gal/acre (U.S.), larval mortality was between 84% and 93% compared with between 39% and 53% in the check plot. Foliage protection was 47%. The results indicate the possibilities of using B. thuringiensis + chitinase to control spruce budworm infestations.

The strong attractiveness of logs infested with female ambrosia beetles, Trypodendron lineatum (Oliv.), to the flying population was sharply reduced after the addition of males. The field response of T. lineatum was greatly reduced when air from logs infested with attractive females was mixed with air passing over logs infested with both sexes. The findings suggest that females keep producing the attracting principle in the presence of males. Males appear to reduce secondary attraction by producing a volatile substance(s) which may be anti-aggregating or repellent in its effect.

Economic injury levels of the alfalfa weevil on alfalfa were investigated in New York State. The dry weight food consumption for the larval stage of the alfalfa weevil averaged 7.34 mg/larva. For every gram (dry weight) of alfalfa consumed, 1.59 g (live weight) in insect tissue was produced. In the laboratory, it was found that insect food consumption could account for only about 50% of the total weight loss in alfalfa plants after 10 days of larval feeding. Therefore, alfalfa weevil damage to alfalfa was more than the larval food consumption, and this was believed to be due to the loss of the plant’s photosynthetic potential. In the field on first growth alfalfa, the economic injury level was calculated to be 56 larvae/stem. First growth alfalfa was less severely injured by alfalfa weevil larvae than our second growth alfalfa infested with equal populations of alfalfa weevils. It was shown that first growth alfalfa was able to compensate for 87% of the insect feeding while second growth alfalfa could compensate for only 50%. Since the alfalfa plant’s capacity to compensate for alfalfa weevil feeding can vary due to environmental conditions and plant characteristics, economic injury levels must be adjustable. To provide more reliability to economic injury levels, we propose that in alfalfa the following seven measurements be made: (1) alfalfa weevil larval density; (2 and 3) parasites and predators of the weevil; (4) rainfall and moisture level; (5) plant nutrients; (6) alfalfa variety; and (7) stage and previous management of alfalfa stand.

The spider fauna of alfalfa was studied at Ithaca, N.Y., in three experimental plots and in nearby fields during 1966–69. As part of an overall study of the arthropod fauna of alfalfa, the spider populations in the study plots were recorded weekly during visual examination of the terminal 6 in. of five stems for 100 plants in each of the plots. Additional information was obtained from sweep-net and pitfall trap collections in the study plots and from sweeping several commercial plantings. The spider fauna of alfalfa was found to consist of 78 species, 10 of which were collected only from the ground layer. Tetragnatha laboriosa Hentz and Dictyna volucripes Keyserling were the most abundant species found in the weekly samples. Notes on the seasonal occurrence, location on the plants, and feeding habits are given for the common species.

Diagnostic characters of Antispila nyssaefoliella Clemens and A. cornifoliella Clemens are discussed. Antispila freemani is described as a new species. Adults and male genitalia are illustrated for these three species.

Seasonal trends of the percentage of nitrogen, phosphorus, and potassium were measured in the foliage of apple trees infested with the European red mite, Panonychus ulmi (Koch), at four population levels created by the action of predators and/or chemical treatment.

It was shown that by early September the concentrations of these nutrients; particularly nitrogen, were significantly depressed by high P. ulmi populations.

In answer to Mansingh’s criticism the value of Müller’s system of dormancies is emphasized. It gives especially a clear differentiation between the obligatory dormancy called parapause, which is under the control of only one environmental factor, and the facultative eudiapause, where different factors are working respectively as inducing and terminating. The carabid beetles are an example that illustrates that no narrow correlation can be found between the distribution of dormancy types and the climatic zones on the earth they live in.

Populations of the fir engraver reached epidemic proportions and then declined to a very low level over the study period (1964–71). However, population density within infested trees showed an inverse relationship to overall population trend. The population trend over the past 40 years was associated to some degree with rainfall deficits and with Douglas-fir tussock moth outbreaks.

The major contribution to total mortality in each generation occurred in the larval, pupal and pre-emergent adult stages, next was adult mortality and infecundity, while egg mortality was of least significance. Mortality and infertility of parent females was mainly caused by nematode parasites although host resistance resulted in a significant number of attack failures. Parasitism by a phorid fly was of minor importance. Nematode parasitism appeared to be density-dependent in relation to overall population size.

Most egg mortality resulted from host resistance which was inversely related to egg density within trees. Other egg mortality occurred in a density-independent manner.

Mortality between larva and brood adult stages was mainly attributed to intra- and interspecific competition. The impact of these factors was directly related to within-tree larval density. Nematode parasitism was related to overall fir engraver population size and to per cent infection of attacking females. Predator activity was weakly density-dependent and mortality caused by resinosis was inversely related to fir engraver density. Parasitism and other mortality factors appeared to be independent of host density.

An hypothesis is presented for the population behavior of the fir engraver; population fluctuations being determined by the quantity of susceptible trees and ultimately regulated by intraspecific competition. Nematode parasitism and interspecific competition were regarded as modifying, and perhaps sometimes regulating, abundance. Areas needing additional study, particularly host-tree physiology are discussed.

The nominal genera Neoscaeva Frey, Rhinoprosopa Hull and Antillus Vockeroth, all from the Neotropical Region, are synonymized with Allograpta Osten Sacken. The previously unknown male of the type-species of Antillus is described.

Twenty new parasite–host records for 16 North American species of Ichneumonidae are given. Hosts were collected in southeastern and interior Alaska.