Eight new species of Scolytidae are described from Mexico. The new species represent the genera Scolytus (2), Carphoborus (1), Chaetophloeus (1), Cnesinus (2), Phloeotribus (1), and Prochramesus (1). New distributional records are given for nine previously described species and notes on the genus Prochramesus are included.

Physiological interactions of n-saturated fatty acids, trans-2-unsaturated fatty acids and their methyl and ethyl esters with pre-imaginal stages of Aedes aegypti (L.) have been described. Differences in the response of the larvae and pupae to the same chemical and also the specific interactions of some chemicals synchronized with a short period during the development of a single stage have been emphasized. Investigations of a homologous series of fatty acids and their derivatives indicate that earlier statements to the effect that their toxicity increases as the series is ascended, and that maximum toxicity is reached in the vicinity of capric and lauric acids, should not be accepted without modifications.

Toxicities and teratogenic effects on Musca domestica L. of methyl and ethyl esters of fatty acids have been described. In general, esters of fatty acids containing 10 or fewer carbon atoms in the chain are toxic and melanogenic. Esters of higher members are less toxic, but melanogenic. However, esters of acids containing 13 or more carbon atoms in the chain show special interactions with insects, and methyl trans-2-tridecenoate has a teratogenic effect on the developing wing of the house fly.

Soaking shredded moss and birch bark samples in a 2% bleach solution for 45 minutes will release attached hemlock looper eggs. Soaking has no deleterious effect on the hatching of larvae or the emergence of parasites. This technique, in contrast to direct examination, results in a significant increase in the number of eggs obtained and a decrease in counting time. It also permits the development of egg sampling techniques for use over extensive areas and the collection of eggs in large numbers.

The paper describes and maps stripe pattern variability in the damselfly Argia apicalis (Say) along the periphery of its southeastern distribution. Two major variations exist. One, the broad-striped form, has a wide, full-length humeral stripe and, in females, a well-developed middorsal thoracic stripe. Broad-striped specimens also possess larger areas of black pattern on the dorsum of the head and, in males, on the eighth and ninth abdominal segments. The second, typical form, has a reduced pattern characterizing populations west and north of southeast Georgia and northern Florida. The southeastern margin of distribution consists of broad-striped populations representing four groups of isolated populations. Isolation results from low interchange between colonies of different river systems and, within the southeast, lack of colonies on lakes, ponds, smaller streams, and river headwaters. One intergradation area between typical and broad-striped populations is known. A discussion follows relating origin of the variability to Pleistocene habitat changes.

Baeopterogyna nudipes n. gen., n. sp., family Mycetophilidae, tribe Sciophilini, from Yukon Territory and Alaska, is described and illustrated. The male has normal wings; the female has wings greatly reduced in size, a condition not previously known in the family.

Culiseta minnesotae Barr and Aedes trivittatus (Coquillett) are reported from Manitoba for the first time. A list of mosquitoes previously recorded from Manitoba is given.

Hoplochaitophorus spiniferus is described from swamp white oak, Quercus bicolor Willd. A key to the three known species of the genus is given.

The female and male of Asca acornis n. sp. are described and illustrated. This species occurs in arboreal habitats in the southern United States. The absence of the most salient diagnostic character of the genus Asca on adults of this species is discussed.

The effects of seven gamma radiation dosages from 5 to 100 krad on all metamorphic stages of the spider beetle, Gibbium psylloides (Czenpinski), were studied. Five kilorads prevented development of adults from treated eggs and larvae. Some adults emerged from the pupal cocoon at all treatment levels except 50 and 100 krad, but their longevity was greatly reduced. Adults were fairly resistant to sterilizing effects of the radiation. Twenty kilokrads was not completely sterilizing to either males or females, but fecundity was greatly reduced. The longevity of treated adults was significantly reduced, but some survived for 20 weeks after a 20-krad exposure. Adults and pupae of this species were more radiation resistant than were most other stored-product Coleoptera.

The food value of two synthetic diets for the fly larva Agria housei inverted between two temperatures, 15 °C and 30 °C. The balance of nutrients, particularly effected by the amino acid and lipid mixtures, glucose, thiamine HCl, and calcium pantothenate, was varied in the design of the two diets so that the rate of larval development axenically on one diet was superior to that on the other diet at 30 °C, but inferior to that on the other diet at 15 °C, relatively; for in any case the rate was slower at 15 °C. Differences between the rates on the diets within each given temperature were statistically significant.

The cells composing the tissue of the prismatic pigmented maculae (PPM) of the pupa of the monarch butterfly (Danaus P. plexippus) are described for the first time and their possible functions in the formation of scales and scale pigmentation in the adult butterfly are discussed.

Parathion was the most effective ovicide for European corn borer eggs. Six other materials gave at least 50% mortality at 100 p.p.m., but 17 had little or no activity. Corn borer larvae were more susceptible to insecticides, and probit-mortality data was determined for 17 materials.

In 1970 and 1971 heavy populations of borer were controlled on sweet corn and peppers by twice-weekly sprays of carbaryl, Lannate, and Phosvel. Furadan applied weekly provided good control, and several of the experimental compounds were effective.

Predation by birds and social wasps (Vespula spp.) on larval colonies of Hyphantria cunea Drury was studied in both natural and artificial populations, and predation by mammals on overwintering pupae in the ground was studied in artificial populations. The species of predators are listed and some important differences in their habits of attack are described. Per cent predation by birds is directly related to the population density of H. cunea over a range of densities, but inversely related after density exceeds this range. When habitat and weather favor rapid population growth, H. cunea "escapes" from the population range in which predation exerts a regulatory influence.

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.

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.

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.

Two bioassays were used to study the effects of the various life stages of a Temperate Zone ambrosia beetle, Xyleborus dispar (F.) (Coleoptera: Scolytidae), on the induction of the ambrosial form of its symbiotic fungus, Ambrosiella hartigii Batra (Fungi Imperfecti).Postdiapause adults and pupae of X. dispar cause a change from the mycelial to the ambrosial form of A. hartigii in culture.

Larvae feed on the mycelial form in vitro, but ambrosia is required by larvae to develop and pupate. One of the main factors inducing the ambrosial form of A. hartigii is probably a secretory product of X. dispar.

Perimones britteni (Jackson, 1913) is regarded as conspecific with, and therefore a junior synonym of, Minyriolus arenarius (Emerton, 1911). Hence, Perimones arenarius (Emerton) is Holarctic. Contrary to common usage, Walckenaera spiralis (Emerton, 1882) is not a synonym of W. vigilax (Blackwall, 1853), the former applying to a North American species and the latter to a European. Cochlembolus formicarius sp. n. is described from nests of the western thatching ant, Formica obscuripes Forel, in Washington State.