The horn fly, Siphonairritans (L.), has been the subject of a considerable amount of study. In general, it seems to be true that the groups of insects that have received the most attention belong to one of three classes: those that are of economic importance, those that are especially adapted to laboratory manipulation, and those that are particularly attractive to collectors. Despite intensive and extensive studies, the economically important horn fly does not land itself very wall to research in the laboratory at the present time.

Spiders of the genus Philodromus are elusive, predatory creatures of fields, orchards, and woods. The name pernix, meaning lively, as applied to one of the large, grey species that frequent weathered bark and wooden structures is in one sense descriptive of the entire group. Although they seem to spend much time in seclusion under bark scales and in similar places, they are fast runners in the open. Their quick stops and starts, in combination with their flattened, grey or brownish bodies, make these spiders difficult both to find and to collect.

The white pine weevil, Pissodes strobi Peck has been the object of numerous investigations since the early nineteenth century, from which an extensive literature has developed. Despite these efforts, the weevil continues to be a serious pest and one of the most important factors limiting successful reforestation with white pine, Pinus strobus L. It has, therefore, become increasingly apparent that detailed studies of the physical and biological requirements of the weevil are necessary before further efforts can be made to protect white pine stands, both natural and planted, from attack by this insect.

Investigations into the effects of aerobic bacteria, belonging to the cereus group, on insects are very numerous and important advances in this field have been made during the last decade. Workers have shown that strains of crystalliferous bacteria, known under the names of Bacillus thuringiensis Berliner and Bacillus entomocidus Heimpel and Angus, are highly virulent and specific to Lepidopterous larvae. Several workers have reported that Galleria mellonella L. has a variable susceptibility to Bacillus thuringiensis Berliner.

A number of nematode species can be found in almost any sample of agricultural soil taken at random. Some of these have long been recognized as the causative organisms of certain diseases in plants and as causing crop losses of economic significance. Recently there has been increased recognition of the importance of this group of parasites. Farmers as well as research workers are coming to realize that reduced yield and diseased conditions may often be laid at the door of the “eelworm”. Intensive and extensive study of phytonematology is therefore in order. Visible evidence can be found in the numerous publications in these fields.

Soil animals, of which micro-arthropods constitute a very high proportion, do not merely play a subsidiary role in the formation of different humus forms, but a most decisive one (Kubiëna, 1955). In order to know more about this role, however, it is necessary to understand something of the biology of these animals. Now, the Collembola are among the most abundant soil arthropods both as regards numbers of species and numbers of individuals, but although some published information on the biology and life-histories of some species exists, it is surprising how little is in fact known.

The family Pyrgomorphidae comprises about four hundred or so known species of grasshoppers, the majority of which are from tropical and subtropical countries, chiefly of the Old World. The morphology, other than that of the phallic complex, has not been critically studied in the course of this work. The following general characters of the group are, therefore, mainly those given by more recent authors such as Slifer (1940a), Laird (1943), Rehn (1953b), Kevan (1955; 1959; 1961a), Dirsh (1956; 1961a) and Helwig (1958). The chief distinguishing features of the family are as follows.

Resistance of insects to control chemicals poses a major problem in crop, food and health protection. WHO has contributed greatly to our understanding of this problem by establishing simple, standardized and reliable techniques for assessing the susceptibility levels of populations of insects of world health importance to current chemical controls. Only by having an extensive record of such levels, at both different times and places, can changes or trends e.g., developing resistance, be detected. Lack of such standardized techniques makes it difficult to ascertain whether control failures are a result of poor application methods or increasing resistance.

The growing use of synthetic chemicals to combat insects of economic importance to man has led to the discovery and wide recognition of changes in the nature of insect populations and of subsequent control failures. Changes which result in inadequate control when an insecticide dosage which was formerly effective is employed are termed insecticidal resistance. Major review papers (Brown 1958, Crow 1960, Metcalf 1955) all conclude that resistance is a result of natural selection taking place with such rapidity that the worker is able to observe the evolutionary processes. Smith (1941) was one of the first workers to call attention to the significance of racial segregation in applied biology.

The recent increase in interest in the biology of field crickets has prompted the author to attempt a revision of the subfamily Gryllinae. The description of new species of field crickets has for the past thirty years been based at least in part on the structure of the male genitalia and most of the new species have had at least the epiphallic portion of their genitalia figured. This practice, unfortunately, has not included the type species of the various genera and furthermore has not been universally applied to the genera in the subfamily. The logical beginning for a revision would thus be a survey of the genitalia of the type species of the various genera.