Foliage of Douglas-fir and grand fir bearing egg masses of the western spruce budworm, Choristoneura occidentalis Freeman, was collected from sites in Oregon, Idaho, and Montana. Later, 4154 of these egg masses were examined in the laboratory. The average number of eggs per mass was 47.5 ± 10.65 (range 23–58). The number of eggs in a mass increased as defoliation of current foliage increased from none to moderate. The average number of eggs per linear millimeter of a single row ranged among sites from 1.24 ± 0.02 to 2.43 ± 0.21. The average number of eggs per linear millimeter of a row was highest (1.99) among the sites studied in Idaho, and lowest (1.58) among the sites studied in Oregon.

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.

Sawfly-resistant bread wheats varied widely among years in resistance to the wheat stem sawfly, Cephus cinctus Nort. Experimental evidence showed that the major factor involved was a reduction in the intensity of sunlight. A reduction in the intensity of sunlight by up to 50%, which was produced by shading the growing plants with cotton sheeting, caused minor decreases in sawfly resistance. More intensive shading with solid-sided cages and with combined light filters of red and yellow caused the plants to become hollow-stemmed and very susceptible to sawfly damage.

Annual variations in sawfly resistance in plants grown in the field from 1949 to 1978 were significantly related to variations in the number of days with measurable precipitation, to the amounts of precipitation, and to the hours of bright sunshine in the period between 25 May and 5 July. These weather variables were significantly interrelated and were important primarily because they indicated the amounts of light received by the plants. A sufficient reduction in the amount of light (particularly during mid-June) significantly reduced sawfly resistance.

In the summer of 1980, gypsy moth populations were monitored in 13 sparsely infested forests in southwestern Quebec; counts of living and dead larvae and pupae were made on 1,870 trees representing 28 deciduous and one coniferous species. Contrary to our null expectations, the proportionate numbers of pupae compared with larvae on the various host species were not equal. Hosts more preferred by larvae were less preferred by pupae, and vice versa. For example, pupae were disproportionately abundant on host species like Acer pensylvanicum L., Carya ovata (Mill.) K. Koch, and Juglans cinerea L. which are not generally favored larval hosts. Conversely, favored larval hosts like Quercus rubra L. and Ostrya virginiana (Mill.) K. Koch carried lower numbers of pupae than expected from the numbers of larvae feeding on them. Such differential utilization of host trees by larvae versus pupae, which can arise either from host-dependent differences in larval mortality or from late instar migration between hosts, may contribute to maintaining the broad polyphagy of gypsy moth larvae.

Adults and deutonymphs of Najadicola ingens (Koenike) are redescribed and larvae are described for the first time. In light of larval, deutonymphal and adult character states, the phylogenetic relationship of Najadicola with genera in the families Pionidae and Unionicolidae is re-evaluated and transfer of the subfamily Najadicolinae to Pionidae is proposed. Original life history information is presented to supplement existing literature. Parasitism by larval N. ingens on an adult chironomid of the genus Polypedilum is reported. The unique behavioural and morphological characteristics of members of Najadicola suggest that mussel parasitism evolved independently from a parallel adaptive sequence in the genus Unionicola.

An assemblage of 24 grasshopper species inhabited a mixed grass prairie site near Livermore, Colorado. Ten species were gomphocerines, 9 melanoplines, and 5 locustines; the gomphocerines represented ca. 80% of total density, melanoplines 15%, and locustines 5%. Grass feeders, gomphocerines and most locustines, made up 85% of total density. The dominant species was Ageneotettix deorum which contributed 52% of the grasshopper density in 1981 and 37% in 1982. The grasshopper population was at outbreak density both years, 60/m2 in 1981 and 36/m2 in 1982. The pasture had never been treated with insecticide or herbicide. The Shannon-Wiener index of ca. 2.00 indicated a high grasshopper diversity.

Adult weevils were tracked in four Michigan Christmas tree plantations using a capture–recapture method. About 40% of 886 marked weevils were recaptured, some as many as 11 times. All weevils were recaptured in the plots in which they had originally been captured, suggesting that weevils disperse slowly in plantations having favorable conditions for weevil growth and reproduction. Weevils congregated near fresh stumps in the spring, and moved to nearby trees in the summer. They rested beneath the trees during the day and climbed on the trees at night. They can be controlled with chemicals and, in some cases, cultural practices.

Tumblers used to remove debris-feeding insects, predators of the leafcutter bee, excess leaf pieces, debris, and plant foliar molds from cells of the alfalfa leafcutter bee were compared. A hand-cranked tumbler removed significantly more material than did five motor-driven tumblers. It also removed more debris as the initial sample weight increased.

The type material, added to the Coleoptera Section of the Canadian National Collection of Insects from 1 January 1974 to 31 December 1980, is catalogued. This new material consists of 416 holotypes, 188 allotypes and 4 neotypes; 2 species are represented by syntypes and 718 by paratypes or paralectotypes. The reference to the original description for each species is cited. All data associated with the specimens are quoted, except in the case of paratypes, paralectotypes and syntypes.

Fossil oribatid mites were recovered from the Paskapoo Formation exposed along the Red Deer River valley near Blackfalds (fossil insect site 1, 12UUP 171 030). The fossils are Late Paleocene (approximately middle Tiffanian) in age (Fox in press). Other adult and immature fossil insects collected from the same locality reported by Mitchell and Wighton (1979) inhabited a mixed forested environment with associated low-energy, shallow, fresh water. The climate at the time of deposition is suggested by Wighton (1980, 1982) to have been warm-temperate to subtropical. The 11 adult and seven immature fossil mites (Fig. 1 specimen no. UAPC6186) are associated with an unidentified fossil insect larva and two chironomid fly pupae on the underside of a compression-impression fossil leaf of “Viburnum” cupanioidea (Newbeq) R. W. Brown (Caprifoliaceae). Most structures on the larvae are obscured, but the size (length 220–240 μm, width 140–150 μm), absence of dark pigmentation, presence of 3 pairs of legs, and general appearance closely resemble oribatid mite larvae (Fig. 2a,b). The adult specimens have several characteristics in common with the extant genus Hydrozetes. The triangular prodorsum lacks microsculpture and narrows to a pointed rostrum (Fig. 2c,d). Examination of the bothridial area in two specimens indicates that the bothridium is reduced and the sensillus is not present. The legs are monodactylous (Fig. 2d,e) and pteromorphae are absent. The notogastral margin is incomplete anteriorly and bears a round, concave area that probably represents the lenticulus. The size (length 495–520 μm, width 325–355 μm) and general habitus of the fossil mites closely resemble those of extant Hydrozetes species.

Fourteen and 16 carbon saturated and monounsaturated aldehydes have been identified as sex pheromone components for the four. species of Heliothis studied to date (Nesbitt et al. 1979; Klun et al. 1979; Teal et al. 1981). With the exception of H. zea (Boddie), the alcohol corresponding to the major aldehyde component, (Z)-1 l-hexadecen- 1-ol (Zl l-16:OH), also has been found in pheromone gland extracts of all species. We report here the identification of Zll-16:OH from pheromone gland extracts of H. zea females and the results of field trapping studies used to assess the behavioral effects of this compound on conspecific males.

En 1980, en faisant l'inventaire des espèces de moustiques de la péninsule de Shippagan au Nouveau-Brunswick, nous avons capturé deux espèces nouvelles pour la province; les dates et les milieux de capture sont précisés. L'identification des culicides s'est faite à l'aide de la clé de Wood et al. (1979). La Flore Laurentienne de Marie-Victorin (1964) a été utiliste pour l'identification et la nomenclature des plantes citées. Les spécimens larvaires ont été prélevés à l'aide d'un filet de type Langeron d'un diamètre de 20 cm, avec lequel une distance prédéterminée a été parcourue. Les larves ainsi prélevées furent comptées en laboratoire et les résultats exprimés en nombre de larves par m3 (larves/m3).

Many instances of pest populations increasing following the application of pesticides to crops have been reported, with natural enemy destruction by the pesticide often cited as the cause (Putman and Heme 1959). Other explanations include a greater food supply available due to the death of competing pest species (Root and Gowan 1978), and direct stimulation of the enhanced species by sublethal doses of a pesticide, evidenced as increased fecundity (Leigh and Wynholds 1980; Boykin and Campbell 1982; Coombes 1983). In Ontario the use of the insecticide azinphosmethyl has been followed by population increases of the green peach aphid (Myzus persicae (Sulzer)) (Founk and McClanahan 1970; Ritcey et al. 1982). Our study was undertaken to determine the causes.