The predatory behavior of Lonchaea corticis Taylor on the white pine weevil, Pissodes strobi Peck, in Sitka spruce, Picea sitchensis (Bong.) Carr., was studied by temporal sampling and dissection of terminal leaders, and by laboratory experiments. L. corticis oviposition occurred when mining P. strobi larvae were consolidating the feeding ring, an event that segregates the weevil larvae into healthy front-feeders and weak, starving "followers." The number of L. corticis within a Sitka spruce terminal was highly correlated with the number of weak and dying P. strobi larvae, but not with healthy larvae.

L. corticis larvae experimentally deprived of dead P. strobi larvae, behaved as an effective predator, consuming both weak P. strobi larvae and healthy pupae, but apparently not healthy larvae. The transition of L. corticis from second to third instar appeared to occur only after sufficient weevils had been consumed. When an excess of prey was present, L. corticis larvae consumed a mean of 2.9 P. strobi pupae over their entire life cycle. In choice experiments, L. corticis larvae searched for and located mining P. strobi larvae, and fed preferentially on P. strobi pupae rather than granary weevil pupae, Sitophilus granarius L. Under certain circumstances, L. corticis could be an important regulatory agent of P. strobi populations.

The genus Carphacis des Gozis (Staphylinidae: Tachyporinae) is revised and recognized as a valid genus rather than a subgenus of Lordithon Thomson (= Bolitobius auctorum). Three species, dimidiatus Erichson, intrusus Horn, and nepigonensis Bernhauer are recognized as valid and transferred from Lordithon to Carphacis. Bolitobius dimidiatus humeralis Melsheimer is considered a new synonym of C. dimidiatus, and B. ruber Malkin and B. intrusus wallisi Malkin are considered new synonyms of C. nepigonensis. All taxa are described and illustrated and maps showing the known distribution of each species are included. A key is presented to aid in distinguishing the North American and only known Palearctic species.

Toxicity and persistence of six insecticides, including three pyrethroids and three organophosphorus insecticides, against Euxoa messoria (Harris) larvae were evaluated. These insecticides were applied to winter rye or tobacco seedlings in the field, and the residues on the foliage were bioassayed in the laboratory. The pyrethroids, cypermethrin, fenvalerate and permethrin, were more effective and persistent, and killed the larvae more rapidly than the organophosphorus insecticides, sulfopros, chlorpyrifos and trichlorfon. The higher rate of cypermethrin and fenvalerate gave a longer period of protection than the lower rate of the same materials and both materials were persistent longer than permethrin. No visible phytotoxicity was found on the tobacco plants treated directly with sulfopros, trichlorfon, cypermethrin, fenvalerate, and permethrin in the 3 years of tests.

Studies in Western Canada from 1974 to 1977 on variations in time and duration of the emergence period after diapause of leafcutter bees, Megachile rotundata (Fabricius), reared at latitudes ranging from 49°N to 58°N showed that bees reared at northern latitudes emerged sooner and the duration of the emergence period was shorter than for bees from the southern latitude. When southern bees were reared in the north, their emergence pattern was similar to the northern strain. However, the change of time to emerge and duration of emergence period of northern strains reared in the south was less pronounced. Number of days to emerge varied inversely with length of cold treatment at 4 °C with greater variance in southern strains.

A crown-boring noctuid, Amphipoea interoceanica (Smith), has suddenly become a serious pest of commercial strawberries in Manitoba. Eggs are laid in August on dead strawberry leaves and hatch in early May. Young larvae feed in the leaf stalks; older larvae bore in the crowns and kill the plants. There are six instars, pupation occurs in late July and adults emerge in August. The plants are first attacked in the second year of growth and by the fifth year the entire crop may be lost.

The genus Deda (Tenthredinidae: Tenthredininae) is newly described for D. ferula n. sp., Macrophya annulipes Cresson, and Sciapteryx coquilletti Rohwer. A key to species is given and the genus is compared with similar genera of Tenthredininae.

Scymnus marginicollis Mannerheim was reared on green peach aphids, Myzus persicae (Sulzer). At 20°–25 °C and a 16-h photoperiod, durations of egg, larval, and pupal stages were about 5, 10, and 7 days, respectively. Adults survived more than 80 days. The ingestion of wax-producing prey was not required for the beetle larvae to produce their woolly wax covering. Larvae fed exclusively by sucking fluids from appendages of the aphid prey. The coccinellid consumed about 16 adult aphids during the larval stage. Adults fed on fluids and tissues of M. persicae. Female adults consumed about five aphids per day, nearly twice as many as did males. The beetle populations increased in July and reached peak abundance in August. The seasonal trend of S. marginicollis suggests one generation per year.

Spray and feeding bioassays of acephate and carbaryl were conducted with each of the six instars of the western spruce budworm, Choristoneura occidentalis Freeman. Dose-mortality regressions were used to estimate overall relative susceptibility. Small differences in overall susceptibility of the six instars to acephate and large differences to carbaryl were observed. Application of carbaryl so that it would be present when second instars emerge from their hibernacula may maximize efficacy by minimizing the tolerance-instar effect. The efficacy of acephate may be relatively unaffected by instar-related changes in tolerance.

One-day-old P1 males of the almond moth, Ephestia cautella (Walker), were irradiated with 5, 10, 15, or 2 krad of gamma radiation and paired with untreated virgin females. Progeny were collected through three generations, and lines were established in theF1and F2 with all possible degrees of inbreeding and outbreeding. Radiation effects were assayed by determining mating success, sterility of pairs, average number of progeny/fertile pair, and sex ratio for pairs with males (U♂ × F1♀ U♂ × F2 ♀), females, or both sexes (F1♂ × F1♀, F2 ♂ × F2 ♀) from each dose. Results showed the greater the initial dose, the greater the reduction in the number of progeny and the greater the male to female ratio. Radiation effects on both F1 males and F1 females were greater than effects on the P1 males, though effects on F1 males were greater than effects on F1 females. Except for extinct lines, partial recovery occurred in the F2 generation though recovery was much greater in F2 females than in F2 males. In each generation males were more affected than females from the same breeding line when they were outcrossed with untreated moths. The greater the degree of inbreeding in irradiated lines, the greater the effect on both males and females. Although a high degree of population reduction occurred only in the F1 generation at a dose of 15 and 20 krad, population models showed inbreeding at the lower doses caused sufficient depression to greatly reduce abundance of a natural population for several generations after a single inundative release of substerilized males.

Thirteen species of parasites were reared from Pikonema alaskensis (Rohwer) larvae and cocoons collected in Maine and 12 species from larvae collected in Nova Scotia. Of the larval parasites, the most common species in Maine were the ichneumons Rhorus sp. 1 and Syndipnus rubiginosus Walley, and in Nova Scotia, the ichneumons Aderaeon bedardi (Provancher), Mesoleius sp., Rhorus sp. 2, and S. rubiginosus. Of the tachina flies, Palexorista bohemica (Mesnil) was more common in Maine, while it and Bessa harveyi (Townsend) were equally common in Nova Scotia. Only two cocoon parasites were reared in Maine, the ichneumon Endasys pubescens (Provancher) and the pteromalid Tritneptis diprionis Gahan. No egg parasites were reared. Parasitism totaled 12.3% in Maine larvae, 16.1% in Maine cocoons, and 46.7% in Nova Scotia larvae.

In the laboratory, endosulfan and phosalone were non-toxic to adult Pterostichus melanarius and Harpalus affinis and of relatively low toxicity to Amara spp. Phosmet was non-toxic to P. melanarius but was toxic to Amara spp. and to a lesser extent to H. affinis. Azinphos-methyl, permethrin, and dimethoate were considerably more toxic to the latter two species than to P. melanarius. Diazinon was toxic to all species and methyl and ethyl parathion were highly toxic to P. melanarius. Bembidion quadrimaculatum was susceptible to most insecticides except endosulfan and phosalone. Mortality in the field generally supported laboratory findings. Diazinon caused the greatest mortality to all species and permethrin caused some mortality to all species. Phosmet was highly toxic to H. affinis and Amara spp. Generally the toxic effects of the insecticides were of relatively short duration.

A key is given to nine species of Macrosiphum (Sitobion) on ferns in North America, including four new species: M. (S.) lambi new species from Athyrium filix-femina (L.) Roth, in Algonquin Park, Ontario; M. (S.) woodsiae new species from Woodsia ilvensis (L.) R. Br., Manitoba and Northwest Territories; M. (S.) clydesmithi new species from "bracken fern" (Pteridium aquilinum (L.) Kuhn), Utah and Oregon; and M. (S.) walkeri new species from Nephrolepis exaltata (L.) Schott., Arcadia, California.

Aerial colour infra-red photographs were used to detect grasshopper damage to cereal grains, determine extent of damage, estimate crop yield, and identify crops. The detection and identification of grasshopper damage was facilitated by the development of a dichotomous key which differentiates grasshopper damage from other crop anomalies. Crop types and yield were determined from correlations between the optical density of the photographs and the biomass of standing crops.

Cost of an aerial survey was estimated at $0.02 per hectare as compared with ground survey cost of $0.20 per hectare. Information provided by an aerial survey of damage has the potential to assist grain growers, extension personnel, and researchers in evaluating the influence of grasshoppers on grain production

A new bioassay unit is described which provides simulated stream conditions for testing control agents against black fly larvae. Attributes include uniform flow, high control survival, and excellent visibility for observing larval behavior. It also possesses the unique advantage of using recycled water, continuously supplied fresh water, or both simultaneously. The unit has performed satisfactorily in assays against black flies using pathogens, parasites, and chemicals. In addition, stream invertebrates from four insect orders have been maintained in the unit.

A simple and inexpensive incubation unit is also described which possesses several of the advantages of the bioassay unit. It lacks the capability for recirculation and is generally less versatile than the bioassay unit; however, it is useful for the maintenance and observation of stream insects.

Idolocoris agilis Uhler is redescribed and a lectotype designated. Three new species of Dicyphus Fieber are described: confusus from Alberta, British Columbia, Colorado, and Idaho; similis from Alberta, British Columbia, Saskatchewan, Ontario, Quebec, New Brunswick, Nova Scotia, Newfoundland, New Hampshire, and New York; tibialis from Alberta, British Columbia, Colorado, and Montana, Left claspers of the four species are illustrated.

Keys to adults and puparia of three Nearctic species are given, with an outline of distribution of each species. Melangyna tenuis (Osburn) and M. cincta, American authors not Fallén, are treated as synonyms of M. triangulifera (Zetterstedt). A lectotype is designated for M. guttata (Fallén). A new species is described from British Columbia.

Natural infestations of cereal aphids caused significant reductions in grain yield in field plots of early and late cultivars of barley, wheat, and oats in southwestern Quebec. Severely reduced grain yields resulted when caged plants of wheat and late cultivars of barley and oats were artificially infested, but early cultivars of barley and oats were less affected. The percentage protein of grain was significantly reduced in all crops, but wheat and late oats were most affected.

In Hemiarctic northern Quebec (55°00′N; 69°55′W), one of the three main herds of woodland caribou (Rangifer caribou) of Central Ungava, cross the lake Delorme area. During their annual migration, caribou make many persistent tracks which serve as mosquito larval breeding sites for four species of snowmelt Aedes. There are no appreciable differences in species composition, the relative abundance and the density of the mosquito populations in these tracks, and in the natural shallow pools of the two bog plant associations (Carex oligosperma and Chamaedaphne calyculata) crossed by the caribou trails.

The distribution patterns of species of Coleoptera occurring in eastern Canada are examined. The following patterns are discussed: eastern ranges, northeastern ranges, amphiatlantic ranges, boreal ranges, subarctic ranges, arctic ranges, and introductions. The historical development of each of these ranges is discussed relative to their expansion from refugial areas.

The effects of aerially sprayed fenitrothion (210 g/ha) and aminocarb (70 g/ha) on several hymenopteran taxa in New Brunswick are reported. Exposure cage experiments showed fenitrothion to cause as high mortality among solitary bees and vespid wasps as that previously reported for bumble bees. Exposure cage experiments under aminocarb sprays revealed no detectably increased mortality for bumble bees, but a significant effect on solitary bees. Experiments in which whole bumble bee colonies were set out in fenitrothion and aminocarb spray blocks a few days before spraying gave comparable results to those from the exposure cage experiments.

A series of comparisons of bumble bee densities in sprayed and unsprayed areas confirmed our earlier finding that populations are greatly reduced after fenitrothion application. Population recovery during the rest of the season appears to be influenced by meteorological conditions. The ecological replacement of early-emerging by late-emerging Bombus species in fenitrothion spray blocks is further documented. No relationship between bee densities and aminocarb application was found.

A method for retrospective assessment of pollinator activity by measuring nectar levels in Clintonia borealis was successfully carried out on a small-scale basis.