Dry-weight changes in the midgut, abdominal fat body, flight muscles, pterothoracic cuticle, and reproductive tract were measured in unfed male Rhodnius prolixus Stål following eclosion and in males fed a single blood meal on day 5 post-ecdysis. Males, which had fed to repletion as fifth instar nymphs, emerged from the nymphal–adult moult with approximately the same quantity of blood solids in the midgut as observed in fully engorged males. Carry-over of the blood-meal from the fifth instar was sufficient to allow the fat body, flight muscles, and pterothoracic cuticle in unfed males to attain over 85% of the weight accretion observed in fed males. The reproductive tract dry weight in unfed adults increased only 60–65% of that in fed adults. Flight-muscle and reproductive-tract development in fed insects reached growth plateaux in 2 and 3 weeks after the final nymphal moult, while cuticle development continued for up to 10 days. It is concluded that R. prolixus males which emerge from fully engorged fifth instars do not require a blood meal in the adult stage to trigger growth processes and tissue development, but if the adult takes at least one blood meal, significant increases in the reproductive-tract dry weight and slight increases in the dry weights of other tissues will occur.

Females of Muscidifurax zaraptor K. & L. produce a smaller percentage of female progeny as the ratio of ovipositing females to hosts (house fly pupae) increases. Delays in oviposition are apparently responsible for the sex ratio change, because they reduce the percentage of fertilized eggs, i.e. female eggs, that the parasites lay. Delays increase in frequency as the parasite:host ratio increases, and result mostly from interference among the ovipositing females; the interference is mostly or entirely physical. Solitary females of M. zaraptor produce slightly fewer though not significantly fewer female progeny when low host densities delay oviposition; more tests would be required to confirm this effect. There is no evidence for differential survival of the male and female parasite larvae on superparasitized hosts.

Additional data on bionomics, geographical distribution, and taxonomy of many species are presented. Cercyon inquinatus Wollaston is recorded from North America for the first time. C. gebieni Knisch, 1925 and C. faeceus Balfour-Browne, 1954 are placed in synonymy with C. inquinatus.

The favorite method of collecting insects is by sweeping, with the contents of the net either dumped en masse into a killing jar or individual specimens removed with an aspirator. In our collecting of Hymenoptera, however, both methods proved inefficient. When using an aspirator to remove specimens directly from an open sweep net many of the larger and swift flying insects escape almost immediately after the net has been opened and before the collector has managed to capture more than just a few. Furthermore, non-target organisms often are inadvertently collected in the rush, including undesirable groups such as spiders which invariably spin webs inside the aspirator and damage the specimens. These problems are overcome if the entire contents of the sweep net are dumped into a killing jar, but this method requires much additional work after the collecting day is over. The days entire collection must be taken back to the laboratory and sifted through to separate the insects from the debris. Without the aid of a microscope many of the microhymenoptera are easily overlooked, often almost indistinguishable from the debris when not moving. If an entire days sweepings has to be processed under a microscope this becomes tedious.

The major component of the sex pheromone of the eastern spruce budwonn was established by Weatherston et al. (1971) to be trans-11-tetradecenal. Subsequently it was found (Sanders and Weatherston 1976) that a small proportion of cis-11-tetradecenal was essential to attraction and indeed was a component of the natural pheromone. In addition Weatherston and Maclean (1974) have shown that the female sex pheromone gland contains trans-11-tetradecenol, a presumed biosynthetic precursor to the aldehyde.

Populations of potato leafhopper nymphs were sampled in two alfalfa fields throughout the summers of 1976 and 1977 in Montgomery County, Virginia. A dichlorvos-carton sampling method was used to collect nymphs from 3-stem alfalfa bouquets. Instars were based on head capsule measurements. The spatial distribution of nymphs generally fit the negative binomial model. Based on this distribution pattern optimum sample sizes were computed. The nymphal population can be reliably estimated within 20% c.v. during most of the alfalfa growth period. Although most variation was shown to be between samples and not between areas in the field, samples should be taken at random over the entire area of the field under study.

Typhlocyba pomaria McA., with two generations per year, damages the leaves and defaces the fruit of apple. It was reduced in numbers in an experimental orchard by the predatory mirid Blepharidopterus angulatus (Fall.) which attacked the second generation. The cold-hardiness of T. pomaria and B. angulatus overwintering eggs, which had mean freezing points of −35 °C and −34 °C respectively, was sufficient to protect these species from winter low temperatures in Nova Scotia.

Swammerdami beirnei n. sp. (Lepidoptera: Yponomeutidae) is described from Vancouver district, British Columbia, and distinguished from the European species, S. pyrella (De Villers) and the North American species S. heroldella Hübner = syn. S. castaneae Busck, also = syn. S. cuprescens Braun by Duckworth (1965). Some biological aspects of the species are discussed.

Descriptions of both sexes are presented for Hybomitra typhus (Whitney) and H. pechumani n. sp., and of the larvae and pupae of the former species.

The effect of depriving female field crickets of conspecific male contact upon the frequency of phonotaxic response to conspecific mating song was tested in Gryllus integer Scudder and G. veletis Alexander and Bigelow (Orthoptera: Gryllidae). In both species, positive phonotaxis was 5 to 9 times more frequent in male-deprived females than in females kept with males. Increased phonotaxis in the former group was apparent with 3 days separation. Addition of G. veletis males to the female-only culture greatly reduced subsequent phonotaxis. As female field crickets sometimes occur in male-free areas in the field, such increased phonotaxis may well be of adaptive importance.

A new genus and species of Heptageniidae (Ephemeroptera) is based on a series of nymphs and reared female adults from the Saskatchewan River, Saskatchewan. Descriptions of female and nymphal Macdunnoa nipawinia n. gen., n. sp., of the subfamily Heptageniinae, are given along with notes on the biology. The genus has no close North American relatives, but is allied to heptageniid genera from southeast Asia.

An ecological study of ground nesting sparrows has been underway for several years at Isle Verte (15 km east of Rivière-du-Loup) Québec, in a hayfield–salt marsh ecotone with an average density of six ground nesting passerine pairs per hectare. In both 1976 and 1977 one brood of Savannah Sparrow, Passerculus sandwichensis, containing four and three nestlings, respectively, were observed to be infested with dipterous larvae which have been identified as Protocalliphora hirudo Shannon and Dobroscky. This constitutes the first record of this parasite in Québec and the first time that the Savannah Sparrow has been recorded as a host. Protocalliphora hirudo was originally considered as a species restricted to western North America (Shannon and Dobroscky 1924) but has since been collected from an unidentified sparrow in Massachusetts (Johnson 1925), on Chipping Sparrow (Spizella passerina) nestlings in New York (George and Mitchell 1948), and the Vesper Sparrow (Pooecetes gramineus) in Ontario (Bennett 1957). Bennett (1957), in his study of Protocalliphora spp. in Ontario, described P. hirudo as an ubiquitous species although most frequently found attacking ground nesting birds in open habitats similar to our study area.

Polyembryony is the development of two or more embryos from a single egg. It occurs normally in parasitic insects, e.g., in Strepsiptera, Halictoxenos (Noskiewicz and Poluszński 1935), and in four families of Hymenoptera: Braconidae, Macrocentrus (Muesebeck et al. 1951); Encyrtidae, Ageniaspis (Marchal 1904) and Copidosoma (Doutt 1947); Platygasteridae, Platygaster (Hill and Emery 1937); and Dryinidae Aphelopus (Kornhauser 1919). In these insects polyembryony serves as a survival mechanism.

On the other hand, sporadic polyembryony has been reported to occur in eggs of the grasshoppers Dociostaurus and Melanoplus (Slifer and Shulow 1947).

The isozyme phenotypes of five enzymes have been found to provide additional characters that distinguish two forms of Hybomitra typhus until recently considered as conspecific. Hexokinase and malate dehydrogenase phenotypes were completely diagnostic for the new species H. pechumani and for H. typhus. Alcohol dehydrogenase, triosephosphate isomerase, and phosphoglucomutase differentiated the two species in terms of their phenotype frequencies but were not completely diagnostic. The genotypic frequencies of triosephosphate isomerase were found to be diagnostic with a probability of 99.8%.

When a few large trees are to be sampled, emergence traps provide more reliable counts of mites that are phoretic on southern pine beetles than either removal of bolts or removal of 100 cm2 bark discs. When a large sample from smaller trees is required, removal of bolts is preferable to removal of disc samples. Emergence traps or bolt samples are preferable to disc samples because: (1) fewer mites are lost during transportation and rearing; (2) mites are not left on the xylem; (3) fewer die from desiccation during rearing; and (4) fewer non-phoretic stages accumulate in the collecting medium.

The green lacewing, Meleoma schwarzi (Banks), is reported from the southern interior of British Columbia. Characters are provided which distinguish this species from other Canadian chrysopids, in particular Chrysopa gravida Banks.

Pandemis heparana Den. and Schiff. is common throughout most of Europe and the Middle East to Siberia, China, Korea, and Japan. It feeds on a wide variety of deciduous trees and shrubs. It is regarded as a minor fruit tree pest in some areas as it can damage flowers and fruit.

Three males and four females from a larger number reared from 87 larvae collected in the Lower Fraser Valley, British Columbia, were identified as of this species by Dr. A. Mutuura, Biosystematics Research Institute, Agriculture Canada, Ottawa. It apparently has not been recorded previously from North America.

Companionate planting is one of many insect control strategies propounded by organic growers. A variety of herbs are purported to possess repellent properties to many insect pests of vegetables (Rodale 1975; Yepsen 1976; Hill 1976; Anonymous 1977a). According to Atsatt and O'Dowd (1976), repellent plants are members of plant defense guilds which prevent herbivores from locating their hosts. Perrin and Phillips (1978) reviewed the elements of natural pest control characteristic of mixed cropping systems and outlined suggestions for transferring these elements to “agronomically acceptable” monocultures. However, very little work has been done to substantiate these claims and field evidence of the protective properties of companionate plants is, therefore, warranted. This becomes all the more important because of the dramatic increase in home gardening recently in North America. It is estimated that 33 million home and community gardens were grown in the United States during 1976 and 1977 (Anonymous 1977b). Here we describe the results of field experiments in which we sought to quantify the effect of companionate plants against major lepidopteran pests of cabbage in southside Virginia.

Banchus flavescens Cress. and Athrycia cinerea (Coq.) were reared each year (1972–1975) from larvae of bertha army worm, Mamestra configurata Walk. (Lepidoptera: Noctuidae), collected during an outbreak of this species on rapeseed in Manitoba. Neither parasite was reared from other Lepidoptera collected at that time from rapeseed; two separate attempts to propagate the parasites on native Lepidoptera other than M. configurata were unsuccessful (Wylie and Bucher 1977; Ewen and Arthur 1976). Since 1975 M. configurata has been rare in Manitoba. In 1976 both B. flavescens and A. cinerea were reared from bertha armyworm larvae from temporary artificial populations on rapeseed at Glenlea, south of Winnipeg. The presence of the two parasites in this locality, where M. configurata was not found during the outbreak, suggested that both B. flavescens and A. cinerea parasitize other lepidopterous species in Manitoba, especially when bertha armyworms are not present.

The growth parameters for cotton (Gossypium hirsutum L.) were examined via optimization studies to determine if the observed values were optimal for the season lengths and weather patterns found in California and Nicaragua. The parameters observed for Nicaraguan cotton were further examined to determine if predation by boll weevil (Anthonomus grandis Boh.) of small cotton fruit (squares) could explain the observed discrepancies. All of the observed growth parameters except the fruit bud production rate for the Acala SJ II variety of cotton which is grown in California appeared to be reasonably optimal for California condition (i.e. boll weevil does not occur in California). By contrast, the parameters for the Nicaraguan variety were sub-optimal if boll weevil was excluded from the analysis, but near optimal if the population dynamics of pest were included.