Life table data from a laboratory strain of Tribolium confusum (DuVal) were obtained for use in deterministic and stochastic models of population growth under optimal environmental conditions. Frequency distributions of mortality, developmental time, and age-specific fecundity schedules taken from experiments conducted at five constant temperatures were transposed onto a physiological time scale measured in degree-days. Data of this detail were necessary for use in models that could predict the growth of laboratory populations of the same strain of beetle reared under optimal conditions.

The concept of degree-day summation was employed in three models of malthusian growth predictive over a range of temperatures. When supplied input data from life table studies conducted at five constant temperatures, the models were able to predict the magnitude and pattern of growth of populations of Tribolium confusum Duval reared under malthusian conditions. The stochastic model, moreover, revealed that the series of chance events found in the course of population growth could explain differences between one population and the next. When computer experiments on the importance of various life table parameters were run, the models revealed the overwhelming importance of time taken to mature on the rate of population growth. The level of fecundity was next in order of importance while population growth was least sensitive to changes in survivorship.

An adult of either Coleomegilla maculata lengi or C. m. medialis ate about 280 mg dry Acyrthosiphon pisum in its lifetime at various constant temperatures. Total food consumption and rate of intake increased with temperature and rate did not vary with age. The average ages attained by field-collected and laboratory-reared adults were greatest at temperatures of 17° and 23 °C, respectively, for C. m. lengi and at 23 °C for C. m. medialis. Neither subspecies laid any eggs at 17 °C, C. m. lengi laid some eggs at 23 °C, and both subspecies laid the largest number of eggs at 25 °C. Fertility as percentage of eggs hatched was lower in both subspecies at 34 °C (30%) than at 23° and 25 °C (100%). Ethanol extracts of teak, cinnamon, clove, guaiacol, and resorcinol were the most effective ovipositional stimulants for C. m. lengi when formulated in water. Exposure to the ethanol extracts of different plants increased the incidence of oviposition by 19% and the number of eggs/♀/day by 36% in C. m. lengi.

Laboratory studies on the biology of the carrot weevil, Listronotus oregonensis (LeConte), were performed at 21° and 27 °C. At 21 °C females laid eggs for 88 days on carrot slices and 94 days on foliage. Egg production per female averaged 156 and 175 on slices and leaves respectively. Eggs hatched after 8.3 days incubation and the larval stage comprising four instars was completed in 19.1 days. The prepupal and pupal stages lasted 3.7 and 9.4 days respectively. The complete life cycle including an average preoviposition period of 17 days was 57.6 days. Development was more rapid at 27 °C, with the complete life cycle taking only 37 days.

The genus Anatis is reviewed and six species are recognized: ocellata (L.), mali (Say), labiculata (Say), halonis Lewis, rathvoni (Lee.), and lecontei Casey. Relevant illustrations and a key to the species are given. Neotypes for mali and labiculata have been selected.

The biology of Cassida hemisphaerica Hbst. (Coleoptera: Chrysomelidae) is given and its suitability as a biological control agent of bladder campion, Silene cucubalus Wibel, is evaluated. Because its host range includes a number of ornamental plants in the genus Dianthus and the adults will feed on economic plants in the family Chenopodiaceae, introduction of C. hemisphaerica is not at this time justified.

In Aedes aegypti, the ’matrone’ substance which caused mating inhibition and stimulated oviposition in females, was present in the anterior secretory region of the male accessory glands. In the divided accessory glands of male A. triseriatus, however, it was present in the posterior glands. The posterior gland substance in A. triseriatus was not species specific. It stimulated oviposition in A. aegypti and caused mating inhibition in A. atropalpus. The secretory substance of the posteriormost region in the glands of both species of mosquitoes was mucin in nature. This mucin substance effectively glued the secretory granules of the anterior region(s).

Mean fecundity of hemlock sawfly females emerging from cocoons collected on heavily defoliated western hemlock trees was significantly less than fecundity of females collected from lightly defoliated trees. Fecundity was highly correlated with female cocoon diameter and female forewing length, but was most highly correlated with both variables combined. Time-saving double sampling techniques are discussed for determining mean fecundities of new samples when mean cocoon diameter and forewing length are known.

Caterpillar dispersal among food plants is difficult to measure directly in field populations. However, the tendency of fifth instar cinnabar moth caterpillars to drop from plants when disturbed is correlated to measured larval dispersal in experimental populations. This easily executed behavioural test can therefore be used as an indirect indicator of dispersal in different populations. The degree of response of first and fifth instar cinnabar moth larvae to disturbance is correlated for eight populations tested, possibly indicating a common agent selecting for the falling reaction among larvae in these different stages of development.

Many insects drop from their food plants in response to disturbance and we suggest that this behaviour might provide a useful tool to elucidate relationships between insect dispersal and resource exploitation.

Glypta meritanae, described herein as a new species, parasitizes the larval stage of the white fir needle miner, Epinotia meritana Heinrich, in Colorado and Utah.

The receptivity of sexually mature Plodia interpunctella females during courtship was quantitatively analyzed. When males approached from the rear, two thirds of the females moved away from them on the first courtship encounter so that only 22% of these encounters led to copulation. In second encounters from the rear, however, 86% of the females turned and accepted the males, and 40% of them copulated. When the males approached head-on there was no observable difference in female receptiveness between first and second encounters; in each case over 90% of the females accepted the males and at least 55% of them copulated. Since the acceptance of the male by the female is dependent on her perception of a male sex pheromone released by scent glands on his forewings, she can probably identify the male immediately in head-on encounters but requires additional time or stimulation to do so in rear encounters.

Characteristics of cephalic structures and spiracles of final-instar larvae of three species of the genus Toxophoroides (Hymenoptera: Ichneumonidae: Lycorininae) are described and illustrated, and a key for their separation is given. As this is the first known information on larvae of the subfamily Lycorininae, characteristics of the group are defined, based only on the single genus studied.

Ascosphaera apis (Maassen ex Claussen) Olive & Spiltoir, the causal organism of chalkbrood disease in honey bees, has now spread to eastern Canada. Scanning electron and phase contrast microscopy showed that A. apis may be differentiated from A. major, with which it has been confused, by the surface structure of spore balls and by differences in the size of nutriocysts and spores. A. major does not occur in North America.

Residue analyses for insecticides were conducted when whole tomatoes and tomato juice were processed from damaged tomatoes that had been in contact with the surfaces of wooden hampers treated with malathion or diazinon. There were 0.18–0.21 and 0.59–0.64 ppm of malathion in whole tomatoes and juice, respectively. No diazinon residues could be detected in whole tomatoes and only traces in juice. The data show that it should be safe to treat tomato hampers with these insecticides in an attempt to control nitidulid beetles that infest damaged processing tomatoes during the period between picking and delivery to the factory.

Male and female adults of Neoacarus lacus n. sp. are described. This species is unique among Neoacaridae in that male adults possess 5 or 6, rather than 3, pairs of genital acetabula, and the adults inhabit a shallow eutrophic lake rather than the interstitial habitat in a stream bed.

Male and female adults of Paenecalyptonotus fontinalis n. gen., n. sp., are described. This is the second known species of Acalyptonotidae, and is unique in that adults have the idiosomal dorsum nearly covered by a sclerotized plate rather than mostly membranous, have 3 pairs of genital acetabula rather than 7 to 16 pairs, and inhabit cold water seepage areas and springs rather than lakes. Discovery of this species contributes to the elucidation of the relationship of Acalyptonotidae to other Arrenuroidea.

In the laboratory, diapause in adult Psylla pyricola Förster was induced by rearing nymphs with exposures to daily photoperiods of 13.5 h or less. The critical photoperiod that induced diapause was not influenced by temperature. Diapause was terminated in laboratory-reared adults and winter form adults collected from orchards in mid-October by exposure to photoperiods greater than 13.5 h. With adults collected from orchards during November, December, and January, diapause was terminated in the laboratory under both short and long photoperiods. With the earlier collections, long photoperiods markedly reduced preoviposition periods but with later collections the effect was not as pronounced because the preoviposition period under short photoperiods decreased markedly with the later collection dates. These results are discussed with relation to observations under natural orchard conditions.

The genus Misumenops F. Pickard-Cambridge, 1900 is represented in the Nearctic region by approximately 20 named species, most of which are restricted to the southwestern United States and northern Mexico. The new species described here brings to five the total known from eastern North America.