All stages of Cricotopus (Isocladius) myriophylli n. sp. are described and differentiated from those of other members of the sylvestris group of Cricotopus van der Wulp. The larval diagnosis for the sylvestris group is emended.

A dose of 4 krad was the most appropriate for sterilizing pupae of Delia antiqua (Meigen) for field release: adult emergence was not reduced, emerging female flies were sterile, and the eggs produced by normal females which had mated with males irradiated as pupae had a lower hatch than those resulting from matings with normal males. Males irradiated as 6- to 8-day-old pupae were fully competitive under laboratory conditions. Continuous scrutiny of laboratory cultures to detect reduction in adult emergence or reduced competitiveness of males is stressed.

Under laboratory conditions adult feeding, ovipositional preference, daily fecundity and longevity, as well as larval and pupal development time and survival of the alfalfa blotch leafminer, were compared on Anchor, Vernal, Iroquois, and Saranac varieties of alfalfa. Although some significant differences were noted, no constant trends were evident when considering all parameters, and rmax values for A. frontella (Rondani) on the four varieties tested were very similar.

Data from field plots confirmed that intervarietal differences of the varieties tested were not of sufficient magnitude to markedly affect the population dynamics of this pest species.

Significant variation in the morphology of late-instar nymphs of Stenonema tripunctatum (Banks) in Lake Huron could not be ascribed to their proximity to warm-water plumes originating from the Bruce Nuclear Power Development, by either multivariate or univariate analyses of size and shape. Major sources of variation in S. tripunctatum were developmental state and sex. Nymphs collected just prior to emergence had low values of transverse measurements in anterior regions (inter-orbital width, prothoracic width), whereas males and females were separated by these measurements and other components of head geometry.

No significant effects of thermal exposure were found in the reproductive development of S. tripunctatum, but this species is most commonly found below depths at which thermal-plume effects are expected. Based on a small but representative sample, ultimate-instar nymphs of Stenonema vicarium (Walker) from a depth of 3 m contained significantly fewer eggs and allocated a significantly lower proportion of biomass (dry weight) to reproduction in locations with higher temperatures.

Sawfly-resistant bread wheats varied widely among years in resistance to the wheat stem sawfly, Cephus cinctus Nort. Experimental evidence showed that the major factor involved was a reduction in the intensity of sunlight. A reduction in the intensity of sunlight by up to 50%, which was produced by shading the growing plants with cotton sheeting, caused minor decreases in sawfly resistance. More intensive shading with solid-sided cages and with combined light filters of red and yellow caused the plants to become hollow-stemmed and very susceptible to sawfly damage.

Annual variations in sawfly resistance in plants grown in the field from 1949 to 1978 were significantly related to variations in the number of days with measurable precipitation, to the amounts of precipitation, and to the hours of bright sunshine in the period between 25 May and 5 July. These weather variables were significantly interrelated and were important primarily because they indicated the amounts of light received by the plants. A sufficient reduction in the amount of light (particularly during mid-June) significantly reduced sawfly resistance.

Female stable flies, Stomoxys calcitrans (L.), from larvae reared on the standard CSMA (Chemical Specialties Manufacturing Association) medium required 5 days of blood feeding before producing their first batch of eggs. When the larval medium was supplemented with 1 or 2% cholesterol, resultant females were able to produce mature eggs after only 4 days of blood feeding. Females from larvae reared on the 2% cholesterol-supplemented medium had slight but significant precocious follicular growth at the time of emergence from the puparium. When blood feeding was restricted, the size at which follicular growth ceased was consistently higher in females fed the cholesterol-supplemented diets as compared with control females.

Conelet abortion in a jack pine, Pinus banksiana Lamb., seed orchard in Oneida County, Wisconsin was caused by Platylygus luridus (Reuter) (Hemiptera: Miridae) and ranged from 51% to 87% with the average 74.5% in 3 of 4 years. Adults preferred to feed on ovules in conelets and were 3 to 4 times more destructive than nymphs. When conelets were protected from this insect by coating the twig above and below the conelet with Tanglefoot®, abortion was below 11%. Other mirid adults including Phytocoris michiganae Knight, Pilophorus amoenus Uhler, Dichrooscytus suspectus Reuter, and Europiella n.sp. confined in cages with conelets did not induce abortion.

Eggs of the red turnip beetle, Entomoscelis americana Brown, and seeds of Candle cultivar of Brassica campestris L. and Regent cultivar of B. napus L. (Cruciferae) were exposed to seven constant temperatures (10°–25 °C). At each temperature, egg hatching occurred about 1.0–1.5 days sooner than germination in B. campestris and 1.5–2.25 days sooner than germination in B. napus. Also, germination took place about ½ day sooner in B. campestris than in B. napus. These data indicated that the eggs of E. americana and the seeds of B. campestris and B. napus respond similarly to changes in temperature. Newly-hatched larvae of E. americana were starved for 0–8 days at 15°, 20°, and 25 °C. Starvation-related mortality was not high until they had been starved for more than 2–4 days at 15 °C and 1–2 days at 20° and 25 °C, indicating that the first instar larva has a relatively-limited capability to withstand starvation. Among the survivors, the developmental times for most of the starved larvae were significantly longer than those for the unstarved larvae, but the weights of the adults from starved and unstarved larvae were similar, suggesting that starvation delayed growth and development, but had no apparent adverse or lasting effects on these processes. An evaluation of the egg hatching, germination, and starvation data and of the atmospheric air temperature and soil surface temperature data for the areas where B. campestris and B. napus are grown in Canada suggested that the first instar larva of E. americana normally should not suffer high mortality due to starvation in growers' fields where volunteer seedlings of these two species are the major larval food.

Six pyrethroids, cyfluthrin, cypermethrin, deltamethrin, fenvalerate, flucythrinate and permethrin, and two organophosphorous insecticides, acephate and chlorpyrifos, were applied to the soil surface in the greenhouse and field to evaluate their effectiveness and residual toxicity against the darksided cutworm, Euxoa messoria (Harris), in Ontario.

Four years of tests indicated that the pyrethroid insecticides were consistently similar in effectiveness and residual toxicity at the rates applied. On air-dry soil surfaces in the greenhouse, the pyrethroids were significantly more toxic and persistent than was chlorpyrifos. On moderately moist soil surfaces in the field, chlorpyrifos was as toxic to the cutworm larvae as were the pyrethroid insecticides, but less persistent. None of the pyrethroids was affected by soil moisture to the same extent as was chlorpyrifos. Acephate-treated soil surfaces, regardless of indoor or outdoor conditions, were less toxic and the toxicity less persistent than with chlorpyrifos-treated soil. Although not statistically different, the high rates of pyrethroids were consistently more toxic and persistent to the cutworm larvae than the low rates of the same materials. All the pyrethroid insecticides have excellent potential as soil treatments for controlling cutworms on tobacco.

A new subspecies of Ornithoptera croesus Wallace, O. c. toeantei, is described from Morotai Island, Indonesia; an annotated illustration of a gynandromorph of O. croesus lydius Felder from Halmaheira Island is presented.

Larvae of species representing 8 genera of the family Aturidae from North America are described, including members of the genera Ljania, Neobrachypoda, Estellacarus, and Aturus for the first time adequately. Larvae of species of Woolastookia, Brachypoda, Axonopsis, and Albia are also described to provide comparative data for these genera. A key to the genera of Aturidae, and preliminary diagnoses for the family, currently accepted subfamilies, and genera are provided based upon larval characters. Information on host associations is reviewed for each taxon. Observations on morphology and host associations of larvae provide the basis for a discussion of the phylogeny of these genera, and a review of the classification of the family.

Parasitized cabbage aphids, Brevicoryne brassicae (Linnaeus), produced fewer offspring than unparasitized aphids. Aphids parasitized by Diaeretiella rapae (M'Intosh) during the first, second, or third instar died before producing any offspring; those parasitized during the fourth instar or the adult stage produced a variable number of offspring. The aphid's survival time was correlated with the rate of development, as measured by the length of the pre-reproductive period. A multiple-linear-regression equation is provided for predicting the mean total fecundity of parasitized cabbage aphids from the host age at the beginning of parasitism and the pre-reproductive period.

Spatial dispersion of potato aphids was studied in fields of processing-tomatoes for 2 years to develop a sequential sampling scheme for the aphid. Potato aphids were found on upper, middle, and lower leaf strata in the percentages 60, 31, and 8. Dispersion was clumped, apterates more so than alates. Among-plant variance was generally greater than within-plant variance. There was a good linear relationship between mean crowding and the population mean and an excellent linear fit between log variance and log mean on all leaf strata for green and pink forms of the aphid and for alates and apterates. The log variance – log mean relationship was used as a basis for sequential sampling.

A simple age-specific energetics (calories or biomass) model for the growth and development, reproduction, respiration, ageing, and intrinsic survivorship as a function of temperature and per capita energy availability for pea aphid (Acyrthosiphon pisum (Harris)) is reported. The ratio of energy supply–demand is used to scale all of the rates in the model. The maximum demand for energy based upon current state values is used to drive the Frazer–Gilbert functional response model (i.e. food acquisition), which is a component of the metabolic pool model used to assimilate energy to growth, reproduction, respiration, and egestion. The extensive data sets on pea aphid energetics published by Randolph et al. (1975) were used to develop the model. As the model estimates reproduction (Mx) and survivorship (Lx) values, extensive published age-specific life-data sets on pea aphids are used to test it. The results suggest:

(1) the lower thermal threshold for development is raised and the upper threshold is lowered as food resources are decreased

(2) the temperature-dependent rate of development is slowed with decreasing energy resources

(3) the size of individuals and reproduction become smaller as temperature approaches the upper and lower thermal thresholds.A simple model for multitrophic level interactions incorporating the acquisition and assimilation functions is presented.

Spruce budworm larvae were subjected to bioassay with Bacillus thuringiensis (Bt) to study the effects of exposure time and assay period on mortality, as well as on the possibility of recovery after a feeding-inhibitory dose. At all concentrations cumulative mortality increased until about day 10 of the assay. Extension of the exposure period from 1 day to continuous (equivalent to a 6 day exposure), resulted in a 500-fold reduction in LC50 (increase in potency) and an equivalent reduction in LT50. Some larvae recover if allowed to feed on diet without Bt even after exposure for 4 days to a very high concentration of Bt. The growth rate of recovered larvae is normal, but the time required for normal growth to resume varies with dose and exposure duration. Equations expressing the effect of exposure duration and dose on mortality and recovery period are presented. The implications of these findings for control of spruce budworm are discussed.

A new genus of Gonianotini, Spinigernotus, is described with Sphragisticus simulatus Barber 1918 as type-species. S. simulatus, known only from New Mexico, is reported from Mexico. The new genus Cordillonotus, and type-species C. stellatus, are described from British Columbia, California, Oregon, and Washington. Cordillonotus is tentatively placed in the tribe Rhyparochromini.

Diet incorporation assays detected no difference in susceptibility of instars IV, V, and VI of spruce budworm exposed to Bacillus thuringiensis, either in terms of dose, LC50, or time, LT50. The hypothesis that the dose–response for larvae of each instar fitted a common regression line was statistically acceptable. Differences in the pattern of changes in larval weight of instars IV, V, VI larvae in response to dose were not detected.

Small plots were sprayed with 5.5, 10.9, 21.9 BIU/ha at times corresponding to peak instar III, early IV, peak IV, peak V, and peak VI. Instar III larvae were controlled less effectively than were instar IV or V larvae which were controlled equally well. Instar VI larvae were also less effectively controlled than instar IV and V larvae probably because a significant proportion had reached the non-feeding prepupal stage before the full effect of B.t. was obtained.

The subgenus Steropus Dejean of the genus Pterostichus Bonelli (Coleoptera: Carabidae) is redefined. The subgenus includes 24 species occurring in the Palaearctic and Nearctic regions. Eight species previously included in Steropus, P. catalonicus K. Daniel, P. ferreri (Español andMateu), P. galaecianus Lauffer, P. ghilianii (Putzeys), P. globosus (Fabricius), P. insidiatrix (Piochard de la Brûlerie), P. madidus (Fabricius), and P. riffensis (Antoine), are transferred to the subgenus Corax Putzeys (formerly considered as a junior synonym of Steropus) which is recognized as a valid taxon. Refonia Casey, with two North American species, Eosteropus Tschitschérine (type-species: Platysma creperum Tschitschérine, present designation), with four Asiatic species, and Steropinus Lutshnik, with one Asiatic species, are placed in synonymy with Steropus. Adult and larval character states of the subgenus Steropus are described. Larvae of Steropus are synapomorphic with those of P. (Corax) madidus and P. (Feronidius) melas Creutzer in having the mandible strongly curved with wide retinaculum in the first instar and a membranous area on antennomere I.

Platylygus luridus (Reuter) causes conelet abortion and reduces seed production in jack pine, Pinus banksiana Lamb., seed orchards in northern Wisconsin. One generation a year occurs and the insect overwinters as an egg that hatches during late May. The nymphs pass through 5 instars within 5 to 6 weeks. Adults were abundant during July and early August 1982. Eggs were laid singly within the phloem tissues of current year's shoots just below the bases of needle fascicles. The nymphs fed predominantly on the tender tissues of shoots or needles. The adults preferred to feed on ovules in the conelets, and conelet abortion resulted. About 74% of the total abortion occurred during adult feeding periods. Conditions favoring P. luridus population increases in the jack pine seed orchards included: densely planted seed orchards on high fertility sites; trees 6 to 10 years old with closed crowns or in shade; vigorously growing trees that were well watered and fertilized. Natural enemies included predators Deraeocoris albigulus, D. (possibly) laricicola, Evarcha nr. hoyi, and Misumenops asperatus.

The last-instar larvae of 22 species of Spilomelini are described and illustrated. Diagnostic characters are given, and a key included, for North American species.