Three new species of ascid mites are described and illustrated: Proctolaelaps subcorticalis, Lasioseius corticeus, and Gamasellodes rectiventris. All are subcortical associates of bark beetles in North America.

A nymph of an homopteran preserved in Cretaceous amber from Cedar Lake, Man., is described. It presents features of two recent families, Cercopidae and Cicadellidae, and so is recognized as a new family of intermediate position. Jascopidae new family contains only Jascopus notabilis n. gen., n. sp.

Laspeyresia cupressana (Kearfott) (Lepidoptera: Olethreutidae) bores in the scale tissue of cones, the healthy phloem tissue of branch nodes and trunks, and damaged sites on plants of certain Cupressaceae and Taxodiaceae. The moth primarily attacks Cupressus macrocarpa Hartw. in coastal California where it passes through two generations annually, one in spring–summer and the other in fall–winter. Several parasites and predators were regularly found associated with Laspeyresia in the cones. Branch and trunk feeding occasionally is severe, but was never observed to cause dieback or tree death. The moth was frequently observed infesting sites on plants damaged by the fungus Coryneum cardinale Wagener.

Biological control attempts on pome fruit in North America, 1860–1970, are summarized and successes and failures reviewed. In all cases, save two, claims in support of successes are lacking. It is concluded that a modern research approach to the study of biological control—including a study of the population dynamics of the host species and of the biotic agent used in control—must be taken. Claims of successes of biotic agents—parasites and predators—in control of pome fruit insect pest populations (stage or generation) must be supported by quantitative multifactor studies. Otherwise the scientific requirements and exigencies (e.g. manipulation of biotic agents with predictability) will not be satisfied.

The following species are treated and new synonymies indicated: Cordylura aea, type unknown; C. cupricrus, = Hylemya coenosiaeformis Stein; C. flavipennis, = Acrostilpna replicata Huckett; C. imperator, = Hoplogaster setipes Huckett; C. tenuior, = Hoplogaster mollicula (Fallén); Anthomyia anane, == Botanophila setigera (Johannsen); A. badia, genus Paraprosalpia; Coenosia spinosa, = Hydrophoria ambigua (Fallén).

Zamischus elongatus n. sp. and male Z. braziliensis Ashmead from Brazil are described and illustrated.

A new classification of dormancy in insects is proposed on the basis of the evolutionary nature of dormancy, its synchronization with the aetiology of the species for their phenological advantage, the nature of ecological adversity, and the consequent physiological and biochemical adjustments. The roles of the above factors in the induction and termination of dormancies are discussed. The inadequacies of all the previous systems of describing various conditions of dormancy are pointed out.All instances of dormancy are divided into three major groups: hibernation, aestivation, and athermopause. Each of these classes is further subdivided into three categories representing a sequence of evolutionary adaptations: quiescence, oligopause, and diapause, in that order of evolutionary development. Depending upon the physiological condition of diapausing individuals or populations, two diapause states are recognized: teleodiapause and ateleodiapause. Each term is defined and discussed with examples.

The number of molted head capsules of Pissodes nitidus is four, but the frequency distribution of the head-capsule widths and lengths of the weevil larvae do not always show four clear separations. It is necessary for more reliable determination about larval instars to count the molted head capsules in the larval gallery.

Range extensions and habitat data are given for two species of Chironominae: Chironomus (Chironomus) atrella (Townes) and Chironomus (Einfeldia) paganus (Meigen) from Saskatchewan. The first is a new record for Saskatchewan; the second is new for Canada.

An anatomical description of the larval and pupal stages of the genus Conophthorus Hopkins is given and illustrated. The description is based on larvae of nine species and pupae of eight, but the strong similarity in all anatomical details suggests that the description will probably cover the remaining species. The most recent addition to the genus, C. banksianae McPherson, is referred to particularly, and the need for a complete revision of the genus is suggested.

After successfully rearing the pale western cutworm, Agrotis orthogonia Morrison, for years in the laboratory such severe mortality developed in the colonies that further nutritional studies were impossible. The symptoms and effects of the disease syndrome are described. Neither steam sterilization of food and rearing equipment nor use of antibiotics in the food prevented disease. A bacterium tentatively identified as Pseudomonas aeruginosa was isolated from dead insects and when injected or fed to healthy larvae caused the disease. Use of a ’clean room’ and associated aseptic techniques for rearing the insects reduced the numbers of microorganisms in the environment and again permitted the pale western cutworm to be reared successfully.

Protein fed to adults of the carrot rust fly, Psila rosae F., enhanced oviposition: the addition of yeast hydrolysate to the sugar diet resulted in a 50% increase in oviposition, giving an average of 75 eggs per female.A description is given of a simple oviposition device, which allows normal oviposition (compared with sand).Carrots planted in sand gave best rearing results when inoculated with eggs 14 days after insertion. Germinating carrot seeds placed on top of the sand improved the rate of development of the eggs to pupae from 40% to 62%.

Twenty-one sympatric species of Carabidae fed on eggs of Euxoa ochrogaster Guenée in laboratory trials. Seven species were demonstrated to have fed in the field on cutworms or pupae of E. ochrogaster and six species fed on cutworms in the laboratory. Carabidae are important as predators of E. ochrogaster but failed to eliminate the prey population in a study area in central Alberta.

Earwig (Forficula auricularia L.) populations infested by the nematode Mermis subnigrescens Cobb were collected from the Ayton area of Ontario, Canada, in 1968 and 1969. Parasitism levels in earwigs from this area ranged from 10.9 to 63% and appeared to be a factor in population control. It is suggested that M. subnigrescens could be used to effect population reduction of earwigs by release of infested earwigs or by distribution of nematode eggs.

An appraisal of population processes in the Colorado potato beetle, Leptinotarsa decemlineata (Say), on its principal host plant showed that the insect has no natural agents that act in a manner that prevent it from overshooting its food supply. It is little affected by weather conditions or predators, and its only parasite, the tachinid Doryphorophaga doryphorae (Riley), is inversely density dependent in its action. Once the beetle has exploited its food resource, the larvae starve and the adults emigrate in quest of other hosts.The analysis of age interval survivals showed that populations are both regulated and disturbed by the principal key factor, adult migration, which is density dependent but overcompensating. A predictive model based on density relationships explained 94% of the variance in population trend.