Entomophthora phytonomi Arthur, a pathogen recognized for many years under the name Entomophthora sphaerosperma Fres. as an important natural control agent in populations of the clover leaf weevil, Hypera punctata (Gyll.), has now been identified from the alfalfa weevil, Hypera postica (Gyll.). Both conidial and resting spore stages are described.

Early in the summer of 1973, the fungus was responsible for an epizootic in populations of the alfalfa weevil throughout much of east-central Ontario. In three study plots, mortality levels in larvae and cocoons ranged from 65–90% and 42–53%, respectively. This suggests that the fungus is capable of playing a significant role in the dynamics of weevil populations.

Eight new species of Amblysellus are described and illustrated: A. cereus n. sp. from Guatemala, A. torqus n. sp. and A. excavus n. sp. from Ecuador, A. dedecus n. sp., A. necopinus n. sp., A. copulus n. sp., and A. macularis n. sp. from Mexico, and A. acuerus n. sp. from North America north of Mexico. A key to the known species of the genus is presented.

Six brands of commercial dichlorvos-vaporizing solids were tested individually in a 28.3 m3 test chamber simulating home conditions to evaluate their effective life. The dichlorvos vapor concentrations developed and maintained by the vaporizers in the chamber, varied from ca. 0.5 μg to 0.005 μg/liter during approximately a 2-month test period depending on the brand and ventilation of the test chamber. Any increase in ventilation correspondingly decreased the level of dichlorvos vapor concentration and vice versa. The vaporizing samples became depleted rapidly at higher than at lower rate of air exchange. At either rate of ventilation (1/3 or 1 air change/h) some of the samples, depending on their potentiality, were completely depleted whereas others produced very low concentrations during the 2-month exposure.

A 70–90 min exposure to a dichlorvos vapor concentration of ca. 0.1 μg/liter gave almost 100% mortality of susceptible and 85% of DDT-resistant caged female house fly, Musca domestica L. However, a similar exposure killed only 16% of the field-collected female house flies. When exposed, as free flying, to a similar concentration it took only 45 and 85 min to cause 95% kill of the susceptible and 85% kill of DDT-resistant house flies respectively. However, a 61/2 h exposure of field house flies to a similar concentration killed only 35.5% of them.

A dichlorvos concentration of ca. 0.1 μg/liter gave 100% kill of Tineola bisselliella (Hummel) larvae and Blattella germanica L. male adults in 6 and 3 days respectively, and of Aedes attopalpus Coquillett adults in a 30-min exposure. However, only 19% kill of Attagenus megatoma (F.) larvae occurred in 7 days with a similar concentration.

Calling by female Lambdina fiscellaria lugubrosa (Hulst) occurred when terminal abdominal segments 8–10 were protracted, exposing an enlarged region in the intersegmental membrane between segments 8 and 9. Histological examination of this region disclosed paired glands situated ventrolaterally in the eighth segment. The glands were presumed to be pheromone glands, and differ from those described for other Lepidoptera, in their paired structure and ventrolateral position. More males were attracted to traps containing virgin females than to empty control traps, but only during the first half of the moth flight. Board and yellow carton sticky traps were superior to 3M and white carton traps. Behavioral observations suggested that the sex pheromone may serve as an excitant as well as, or instead of, an attractant, stimulating the male to searching activity.

In unsprayed apple orchards in Ontario the sex ratio (female:male) of mature codling moth larvae was negatively correlated with total moth numbers, per cent fruit damage, and the fecundity of first generation females. Changes in both the larval and adult sex ratios were indicative of the tendency of moth populations to increase or decrease from one season to the next.

Calling by newly emerged female Lambdina fiscellaria lugubrosa (Hulst) began the first evening and commenced 15 h after the onset of light in nature and in a 14L:10D photoperiod regime in the laboratory. Copulation began 0.5 to 1.5 h later, and moths remained in copulation an average of 3.45 h. The internal reproductive system is typical of ditrysian-type Lepidoptera. Mating usually resulted in the transfer of a single, spheroid spermatophore with a long collum. The spermatophore was placed in the bursa copulatrix in such a position that spermatozoa could leave through the aperture into the ductus seminalis. The greatest mating success occurred between 2- to 4-day-old males and females up to 4 days old. Maximum oviposition occurred on the day after mating. Numbers of eggs maturing and being laid were increased after mating. Mean longevity of mated and unmated females in the laboratory was 18.1 and 20.8 days, respectively. Mating success was greatest at a 6:1 male to female sex ratio, and progressively less at a 1:1 and 1:6 sex ratio. Males mated only once in a 24-h period, but were capable of multiple mating. Females usually accepted one spermatophore but occasionally up to three were found.

The life history of Monarthrum fasciatum was studied from 1971 through 1973 on oak in Missouri. Three generations of the beetle were observed each year and the measurements of the life stages and the gallery components were recorded. The female to male ratio was approximately 2:1. No relationship was found between oak-wilt-killed trees and M. fasciatum.

Aggressive behavior of the western cherry fruit fly studied both under laboratory and field conditions indicates that males are extremely territorial, especially in the field, where they do not tolerate the presence of another fly on a cherry unless the invader is a mating partner. Under confined laboratory conditions, the sense of territoriality was markedly reduced. Aggressive behavior in this insect included a wing jerking display, head-on collision, and "boxing" (fight involving prothoracic legs).

The North American species of Choroterpes are discussed and Neochoroterpes n. subgen. is established for C. mexicanus n. sp., C. crocatus n. sp., and C. kossi n. sp. A distribution map is included for the southwestern species of Choroterpes s. str., and distribution map, key to the nymphs, descriptions of the known stages, and figures are presented for the species of Choroterpes (Neochoroterpes).

Echthromorpha agrestoria pascuensis is described from Easter Island (Isla de Pascua). It is a rather melanic race of this extremely widespread species.

The taxonomic identities of the Lonchaeidae described by Bigot, i.e., Lasiops nitens from Europe and Ophyra andina from Chile, are established from their holotypes in the Hope Department of Zoology collection, University Museum, Oxford, England.

Captive colonies of Vespula arenaria (Fabricius) and Vespula maculata (Linnaeus) were placed in the field during the summer and fall of 1972. The adults were free to forage, and the colonies developed normally. Nest temperatures were recorded at mid-afternoon, 6 days per week. Once each week, colonies were confined, brought into the laboratory, and placed in a cold room at 5 °C for 4 h. At the end of this period, the nest temperatures were recorded and the colonies returned to the field. Under field conditions, V. arenaria colonies maintained an average daytime nest temperature of 31 °C, and V. maculata colonies maintained an average daytime nest temperature of 29 °C. As they developed, colonies of both species were increasingly capable of resisting cooling at an ambient temperature of 5 °C. This ability to thermoregulate under extreme conditions peaked in early August for V. arenaria and in late August for V. maculata. In both species, the decline in the ability to thermoregulate was associated with the production of reproductives. It appears that the major function of thermoregulation in these two species is to provide a favourable temperature for the development of the young rather than to provide the colony with protection against low ambient temperatures.

Ten new species of Trichobius are described from the Neotropical Region: T. intermedius (Dominican Republic, Haiti, Bahama Islands, Cuba, Jamaica, Puerto Rico, Virgin Islands, Lesser Antilles, Mexico, Guatemala, Honduras, and El Salvador); T. neotropicus (Dominican Republic); T. cognatus (Dominica and Cuba); T. wenzeli (Cuba); T. dusbabeki (Cuba); T. cernyi (Cuba); T. frequens (Cuba, Dominican Republic, and Jamaica); T. macroti (Cuba and Bahama Islands); T. robynae (Puerto Rico); and T. dominicanus (Dominican Republic).

The Holarctic genus Symphoromyia, the biting snipe flies, is discussed and a taxonomic history of the group is reviewed. Five subgenera including Symphoromyia s. str., Paraphoromyia Becker, and three new subgenera, Axinicera, Pogonaria and Ochleromyia, are established and a key for their separation and recognition of included species-groups is presented. Each subgenus and its associated species-groups are discussed and compared with respect to distribution, morphology, and evolutionary trends. Known aspects of biology for the genus are presented to include: (1) a generalized life cycle; (2) immatures; (3) natural enemies; (4) female biting activity; (5) male swarm behavior.

The visual–acoustic signal system of Dissosteira carolina (L.) is described from field and laboratory observations. The form and occurrence of seven visual signals, seven visual–acoustic signals, and three behaviour patterns with possible signal function are described. The functions of these signals are discussed and a new functional category (interaction terminating) is proposed.

Trypsin has been partially purified from the midguts of Glossina morsitans. It is inactivated by tosyl-l-lysine chloromethyl ketone, phenylmethane sulfonylfluoride, and 2-mercaptoethanol. Mammalian sera inhibit G. morsitans trypsin in vitro. Sheep serum contains at least two inhibitors of G. morsitans trypsin and a high molecular weight material which protects against serum inhibition. Very low levels of trypsin inhibitor are found in G. morsitans primary excreta and in the salivary glands, Malpighian tubules, and anterior midguts of unfed flies. High concentrations of trypsin inhibitor are found in the anterior (non-digestive) section of the midgut for at least 48 h after flies fed on goats.

Metrioptera (Roeseliana) roeselii (Hgb.) was first introduced into the Montreal, Que., area before 1952. By 1965 it had been collected in western and southern New York State. This paper records it from Maine, Massachusetts, and New Hampshire for the first time, and discusses the populations. Eventual establishment of M. roeselii over all of New England is predicted.

The new genus Dioryctriodes is described for D. daelei n. sp., from Italy. This species closely resembles Dioryctria taiella Amsel in maculation but not in palpal structure or genitalia. D. taiella is referred to a new species-group of Dioryctria.

The reproductive behaviour of Camnula pellucida (Scudder) is described. This includes some general information on congregation on a field breeding site as well as detailed descriptions of courtship, copulation, and oviposition behaviour. Differences in behavioural patterns from those previously outlined for another major grasshopper species are tabulated.