Intertidal Chironomidae (Diptera) are represented on the coast of British Columbia by Paraclunio alaskensis Coquillett and Saunderia pacificus (Saunders), S. marinus (Saunders), and S. clavicornis (Saunders). These species inhabit a variety of rocky shore types, being found on exposed as well as protected shores, but are not present on exclusively sandy shores. Their range extends at least to the Queen Charlotte Islands, the most northerly area collected during this study. S. clavicornis is the most ubiquitous of the four species while S. pacificus is the rarest.Within their habitat larval distribution is contagious and is well described by the negative binomial distribution. It is probable that their clumped distribution is due to environmental factors rather than active aggregation. Larval densities of 4316/ft2 were recorded for Saunderia spp. and 1613/ft2 for P. alaskensis. Larvae fed on green algae and diatoms and it was demonstrated that they can select certain groups of diatoms from the substrate.Adult emergence occurs throughout the year but is most intensive in the fall and least in the late spring and summer. Generally, larval population fluctuations follow adult emergence trends. It is hypothesized that larval population fluctuations are caused by a combination of overlapping multiple generations and differential larval growth rates at fluctuating temperatures, coupled with varying lethal environmental factors at different times of the year. Developmental times at 10 °C from egg-laying to adult emergence was 110 days for S. clavicornis, 150 days for S. marinus, and 204 days for P. alaskensis.

Lesser peachtree borers, Synanthedon pictipes (Grote & Robinson), were the principal insect species collected from caged peach wood, and American plum borers, Euzophera semifuneralis (Walker), were the second most common species. However, the population was diverse: 8 orders, 99 families, 222 genera, and 239 species were represented. Wood-boring insects were represented by 3 orders and 11 families. Many insects were apparently transients and were on the peach wood for protection during the dormant season when the peach wood was cut.

Dichrooscytus elegans Uhler is redescribed and its status discussed. Four new species of Dichrooscytus are described: minutus, flagitiosus, and taosensis from New Mexico, and texanus from Texas. Male genitalia of the species are illustrated, host plants are given, and relationships to other species in the genus are discussed.

The diel periodicities of emergence of seven species of chironomids from two ponds in the Hazen Camp area (81°49′ N., 71°18′ W.) are considered in relation to physical factors. Emergence of all species is greatest during the middle part of the day: an increase in water temperature induces emergence and a decrease inhibits it, whereas changes in light intensity, ultraviolet radiation, sunshine, and wind appear to have no effect on the diel emergence pattern. In a shallow pond, males emerge slightly earlier in the day than females in some species. In the same pond also, emergence, particularly of females, is sometimes distinctly bimodal. In a deeper tarn where the diel temperature fluctuation is very small there is a single peak, which is less pronounced than in the shallow pond.That temperature controls the periodicity of emergence implies that short-term temperature changes which may inhibit adult activity are of great importance in the high arctic. At these latitudes, changes in light intensity evidently do not reliably indicate to the emerging organisms temperatures which fluctuate near critical thresholds for activity.

The species of the chalcidoid genera Aphelinus Dalman, Mesidia Foerster, Mesidiopsis Nowicki, and Protaphelinus, new genus, are solitary endophagous parasites of aphids. Their classification is discussed. And a key to the genera is given based on adult characters.

Special emphasis in the revision is on the known Canadian representatives and species that are likely to be found in Canada. The first part of the revision deals with genus Protaphelinus. The type-species, P. nikolskajae (Jasnosh), is described in detail and illustrated. New information on distribution and host ranges is provided.

Microctonus stelleri Loan is described as a new species. This euphorine braconid occurs in France, Germany, Sweden, and Russia. It is umvoltine and its only known host is the alfalfa weevil, Hypera postica (Gyllenhal). In the spring the mature parasite larva issues from the overwintered adult host and forms a white cocoon in the ground litter. In about 2 weeks the adult parasite emerges, mates, and oviposits in larva of the alfalfa weevil. The parasite egg hatches and the first-instar larva remains within the host until the following spring. In northern France M. stelleri was the dominant parasite in overwintering adults of H. postica. Parasitism ranged from 0 to 13% though it was usually less than 6%. Laboratory studies showed that M. stelleri females live longer, have a higher rate of oviposition, and parasitize more hosts than females of M. colesi Drea, a parasite of the weevil in the United Slates. A technique is described for the recovery of M. stelleri from adult alfalfa weevils. From 1966 to 1970, 4387 parasites were imported from France and released at 24 localities in the United States.

Catinathrips kainos O’Neill and Frankliniella vaccinii Morgan overwinter as adults in the soil and first appear on lowbush blueberry plants in mid- to late May. C. kainos was the predominant species on the plants in the spring in six Maine locations. The peak of nymphal abundance occurred in mid-July. It is believed that C. kainos migrates into the soil to complete development while F. vaccinii becomes an adult on the blueberry plant before migrating into the soil. F. vaccinii adults were found to be much more numerous on the plants in late July and August than C. kainos. Although only a few C. kainos males and no F. vaccinii males were noted in the spring, a 3:4 ratio of male to female F. vaccinii adults was present on the plants in August and about the same adult ratio of C. kainos was discovered in the soil in mid-August. The depth at which C. kainos winters in the soil appeared to be centered at 2.5–3.5 in.

Within white spruce stands near Fairbanks, Alaska, and on the Kenai Peninsula, Alaska, Dendroctonus rufipennis, Ips spp., and Trypodendron lineatum disperse in late May and early June; other scolytids fly during June and July. Flight in interior Alaska precedes by about 2 weeks that on the Kenai Peninsula. Mean daily temperatures during spring and early summer are generally warmer in the interior than in coastal areas. There was a large increase in the total number of beetles in a thinned area, mostly of Dryocoetes affaber.

Samples of the egg, larval, and pupal stages of the saddled prominent, Heterocampa guttivitta (Walker), were obtained from infestations of this defoliator in six northeastern states. Seventeen species of primary parasites were recovered, 11 are new records for this host. A key to adult parasites is presented.Apparent parasitism of the egg stage by Telenomus coelodasidis Ashm. and Trichogramma minutum Riley varied from 30 to 76% and 1 to 20% respectively. Aggregate apparent mortality ranged from 40 to 78%. As a rule, egg parasitism was highest in the upper crown of both sugar maple and beech. The developmental stages of parasitized eggs are described and illustrated.

Two species of larval parasites were recovered: Phobocampe pallida (Cush.) from instar III and Eulophus anomocerus (Crawford) from instar V. Parasitism by each species was always less than 1%.Cratichneumon sublatus (Cress.) was the only pupal parasite found in all of the infestations examined. Parasitism ranged from 1 to 17% under outbreak conditions to as much as 32–57% the year following a collapse of the host population. A new species of Patelloa (Tachinidae) was recovered from pupae in Maine and New York. Parasitism by the latter ranged from 3 to 7%. Ten species of Ichneumonidae and one species of Sarcophagidae were also recovered from the pupae.

The external and internal female genitalia of the North American species comprising the Cicindela maritima group are described and figured. An identification key based on these structures is provided. A phylogeny based on the female genitalia is postulated for the group.

Although heterogony has yet to be proved for the oak gall producing species of Cynipidae, Plagiotrochus tumificus O.S. and P. scitula Bass., the laboratory rearing of the male and female individuals from the vernal galls of these two species indicates that the mother insects in the former species are mostly amphitokous, while those in P. scitula are arrhenotokous and thelytokous. Amphitoky is shown for Callirliytis operator O.S. which is known to be heterogenous.Cynipid inquilines and chalcid parasites were reared from several cynipidous oak galls in the area. The inquiline and parasite fauna of any particular gall depend on the form of the gall and not on the species of the gall producing cynipid. None of the inquilines and parasites reared in this study is identical with known palearctic species. Most individual inquilines and parasites emerging from the vernal galls emerge in the summer, but a few overwinter in these galls and do not emerge until the following spring.

The preparation of Simulium venustum embryos for Scanning electron. microscopy is described.

Male apple maggot flies, Rhagoletis pomonella (Walsh), were present on ceresin wax domes (the site of oviposition and the site of assembly for mating) in much greater relative frequency when caged with 1 or more females or with several other males than when caged alone. Field and laboratory experiments subsequently revealed that a principal stimulus eliciting this greater degree of male assembly was an unidentified chemical(s) deposited on the surface of apples and ceresin domes by both sexes (but in greater amount by mature females) causing arriving males to spend up to twice as much time there as on untreated fruit. The presence of the chemical did not elicit any greater attraction of males to the fruit. The consequence of the longer male residency on domes with the chemical was male aggregation and an ensuant higher frequency of mutual encounter and attempted copulation than on untreated domes. While the chemical acts to arrest males, we theorize that mere detection of its presence may be sufficient to cause males to remain in the vicinity and watch for females.

Nine new species of Dichrooscytus Fieber are described from North America: aztecus and toltecus from Puebla, and mexicanus from Durango and Coahuila, Mexico; longirostris, ochreus, and rubromaculatus from California, brevirostris and dentatus from Arizona, and alpinus from Colorado. Male genitalia are illustrated, host plants are given, and relationships to other species in the genus are discussed.

The genus Megasoma Kirby as it occurs in North and Central America is discussed, and the taxonomic history of this group in this area is reviewed. A key is presented to aid in the separation of the 10 forms currently known from these areas, as well as one species that may be taken in the future. Each species is illustrated and discussed. Three new species, Megasoma sleeperi from Southern California, Megasoma cedrosa from Central Baja California, and Megasoma lecontei from Southern Baja California, are described.

Populations of wasps and bees are larger and more diverse in areas of recently disturbed boreal forest than in non-disturbed areas. Population differences are correlated directly with light penetration which also results in a larger array of pioneer ground cover. The ground cover provides abundant floral forage for the bees and adequate lepidopterous prey for the wasps. The regeneration of the forest results in a decline in the quantity and diversity of the ground cover and the attending aculeate populations. Results from timed census studies, glass-pane barrier traps, and trap nests reflected similar relative attractiveness of the study sites to wasps and bees.

In the laboratory, the mean number of eggs laid per female of the dark-sided cutworm, Euxoa messoria (Harris), fed on honey solution was 1303.8; when given water alone 261.3; and 86.4 when held without food or water. Adult food significantly increased the longevity and oviposition period and reduced the pre-oviposition period. There was no significant difference between the weight of male and female pupae. The weight of the female pupae was significantly correlated with: the oviposition period; the number of eggs laid; the longevity, except moths fed on honey solution; but not the pre-oviposition period, regardless of food taken as adults. Females fed on honey solution mated successfully, 30% of them more than once. When given water or nothing the number of mated females was reduced. Dissections showed that adult food accelerated the development of eggs and increased the fecundity potential.