There are five known North American species in the genus Hylobius; H. pales (Hbst.), H. congener Dalla Torre, H. pinicola (Couper), H. radicis Buch., and H. warreni Wood. In recent years four of these species have increased considerably in economic importance in central and eastern Canada and the eastern United States; H. pales and H. radicis attacking pines and H. pinicola and H. warreni attacking spruces and pines. H. congener occurs only in small numbers and little is known about its ecology. It is important, therefore, to be able to separate these species readily in the field.

Cocoons of winter moth, Operophtera brumata (L.), reared from larvae collected in Europe, were imported to obtain insect parasites for release in Canada. Normally the sequence of handling the host cocoons consisted of: summer storage (July to October); autumn storage (October to December) during which host emergence occurred; winter storage (January to May); and, finally, a period of incubation (May to June) to obtain in time for release against the larval stage of the host.

The effects of fiood od the fecundity and longevity of the adults of hymenopterous parasites vary remarkably, not only between species that are host feeders and those that are not host feeders, but also within these groups. It is known, for example, that the females of Itoplectis conquisitor (Say) develop only few eggs without feeding on body fluids of their host. In the present investigations it is shown that the females of Scambus buolianae (Htg.) are not able to deposit any eggs without first feeding on the tissues of their host. Such information is important for the successful establishment of newly-imported parasites.

A midge, Contarinia oregonensis, is one of a number of species of insects which causc seed losses in Douglas fir, Pseudotsuga menziesii (Mirb.) Franco. In recent years it has been reported causing more damage than any other single species of Douglas-fir cone insect in western Washington (Johnson and Heikkkenen. 1958). This has been the situation on Vancouver Island also.

The species bas described by Foote (1956) from specimens taken in Oregon in 1916.

Siphona irritans (L.), commonly known as the horn fly, is a serious pest of cattle. In southern Alberta, ten thousand flies have been counted on a single host animal. Properly conducted control studies require the establishment of a permanent laboratory colony. Previous attempts to establish such a colony had not been successful (McLintock and Depner, 1957) as more information about the biology of the fly was needed. The results presented in this paper will help provide this information.

In a survey of wood-feeding Anobiidae occurring in the Northeastern United States and adjacent Canada, a species of Ptilinus was found which the author believed to be new and for which the trivial name friendi was proposed (Simeone, 1960). However, having had the opportunity during the summer of 1960 to examine and collect European species at the Forest Products Research Laboratory, Princes Risborough, England and at der Forstliche Bundes-versuchsanstalt Mariabrunn in Schönbrunn, Vienna, Austria, the author now believes his specimens to have been introductions of the common species, Ptilinus pectinicornis L. In view of rhe economic importance of this species in other parts of the world, it seems advisable to describe in some detail the adult male and female as well as to compare some of the characteristics whereby the insect can be distinguished from closely allied species.

The onion maggot, Hylemya antiqua (Meig), has three distinct generations a year in Canada (Armstrong 1924, Hammond 1924, Baker 1928, Lafrance and Perron 1959), and usually two generations in England (Miles 1955). In Canada the three generations overlap considerably and adults of each generation are observed in flight in late summer (Perron et al. 1953). It is the most important pest of onions (Matthewman et al. 1950, Hudon and Perron 1956), and the first generation is the most injurious to the onion plants (Kendall 1932, Miles 1953).

In studies on introduced parasites of the European pine shoot moth, Rhyacionia buoliana (Schiff.), in Waterloo County Reforestation Area, near Elmira, Ontario, casual observations showed that some stages of the shoot moth were attacked and eaten by several arthropods. Preliminary studies were initiated in 1958 on population estimates and feeding activity of five predatory groups and were resumed on a larger scale in 1959 with six groups. Results of these studies are described below.

La distribution géographique circompolaire et très étendue de la mouche à scie du peuplier comprend toute l'Europe et la partie septentrionale de l'Amérique du Nord. Au Canada on a signalé sa présence de l'Atlantique au Pacifique.

Dans le Québec, cet insecte n'avait jamais été signalé cornme très nuisible avant 1956, alors qu'il se multiplia soudainement d'une façon excessive occasionnant des défoliations importantes sur les peupliers ornamentaux, dans certains secteurs de la ville de Québec.

Previous work by Kinghorn and Chapman (1959) has shown that in coastal British Columbia, the ambrosia beetle Trypodendron lineatum hibernates in the forest litter or duff at various distances within forest edges in the vicinity of brood logs. It was pointed out that further study was required to determine the characteristics of the optimum hibernation sites. It was mentioned that stand density, shade, aspect, slope, and the nature of the duff might be factors controlling the selection of the place of hibernation. The base of trees and the relatively deeper duff, characteristic of this situation, was reported to be the location of the larger populations of hibernating beetles although the level of population was found to vary greatly both from tree to tree and in depth within different forest edges.

The family Opomyzidae is composed of small (2.0 mm.-4.4 mm.), slender, usually brown or reddish flies; the wings have at least an apical spot and are usually more heavily marked. Several species of the genus Geomyza have the wings reduced and are nearly flightless. The few species whose larvae are known feed in grass stems. Some are of minor economic importance in Europe but none have been so reported in North America.

The name Syneta is usually attributed to Lacordaire, who was the first to publish it with a description (1845, Mém. Soc. Roy. Sci. Liége 3:226). It has also been attributed to Dejean, for it first appeared in the third edition of his Catalogue des Coléoptères (1837, p. 385) where it is ascribed to Eschscholtz. Barber and Bridwell (1940, Bull. Brooklyn Ent. Soc. 35: 1–12) showed that such names were often validated by publication in the Dejean Catalog and that the chrysomelid names validated there should be attributed to Dejean, except those ascribed there to Chevrolat.

The larva of Argyresthia laricella Kft., the larch shoot moth, bores in the shoots of larch killing the apical portion. It has been collected from tamarack, Larix laricina (DuRoi) K. Koch, European larch, L. decidua Mill., and western larch, L. occidentalis Nutt., but not from Japanese larch, L. leptolepis (Sieb. and Zucc.) Gord., nor alpine larch, L. lyalli Parl., although Japanese larch trees were examined at Fredericton, New Brunswick, and near Burlington, Vermont. This insect has never been considered a serious pest.

The predacious mites of the subfamily Phytoseiinae are common predators of the phytophagous mites in apple orchards in Nova Scotia. There is little information in the literature on the value of these predators in the control of phytophagous mites or on the food necessary for their development and reproduction. Ballard (1953) found that at 78°F. at least two males of Tetranychus bimaculatus Har. were required daily by Typhlodroms fallacis (Garm.) to complete the protonymphal or the deutonymphal instar. The males and mated females consumed daily an average of 3.9 and 7.5 males respectively from the larva1 to the adult stage. Chant (1960) found that T. pyri required 25 larvae of Panonychus ulmi (Koch), during 26 days to complete development at 64°F. in the absence of plant material or free water. These authors did not study the effects of different amounts of food on the development of these two species of phytoseiids.

The objective of this study is to describe the copulatory and ovipositional behaviour of Hetaerina americana and H. titia, and to depict any differences in such behaviour as may exist between these two species. It is quite important in such studies to understand the mechanisms which assure conspecific mating. Both americana and titia are found breeding together on many of the streams of central Texas. Williamson (1906) pointed out that species in which the abdominal appendages were very similar often had sexually dimorphic and/or specifically distinct wing coloration, while species with clear wings had quite distinct abdominal appendages. These different wing patterns were suggested as functioning in species recognition for conspecific mating. Buchholtz (1951, 1955) experimentally verified that the females of Calopteryx splendens recognize and respond to males of their own species through a set of optical stimuli including the color pattern of the wing. Loibl (1958) and Krieger and Krieger-Lobl (1958) experimentally demonstrated that in Lestes dryas, L. sponsa, Ischnura elegans and I. pumila, all of which have clear, colorless wings, the species recognition factors are the shape of the abdominal appendages and body coloration. Williamson's early inferences appear to have been well documented.

Aptesis basizona (Grav.), a hymenopterous parasite of Diprion pini (L.), D. similis (Htg.), Neodiprion sertifer (Geoff.), and other Diprionidae in Europe, was Propagated for several years at Belleville, Ont., for release in biological control programs (Green, 1938), and for use as an experimental insect. It was observed that oviposition was reduced by lack of food and by change of food from raisins to a mixture of sugars and ager (Finlayson and Green, 1940). Fecundity of the females was greater when adults were fed on fresh, unpasteurized honey than on raisins (Finlayson and Finlayson, 1957). Both raisins and honey contain protein, in the proportion of about 8:1 (Anon., l945), so that it is unlikely to be a factor in the difference. As sugar content of raisins is about 73 per cent (Sun Maid Raisin Growers of California, in litt.) and of honey about 79 per cent (Watt and Merrill, 1950), it appeared that mineral trace elements or vitamins in the food might be responsible for the difference in the oviposition. Both raisins and honey contain potassium, chlorine, sulphur, calcium, phosphorus, sodium, magnesium, silica, iron, manganese, and copper, but the latter two are minor elements in raisins (Sun Maid Raisin Growers of California, in litt.; Apiculture Section, Entomology Research Institute, Ottawa, in litt.).

The pine engraver, Ips pini (Say), is one of the most common bark beetles found in pine and spruce in eastern Canada. Clemens (1916) studied its biology in New York State, and more recently, Reid (1955) reported the seasonal development of this beetle in Alberta. Prebble (1933) discussed the larval development at Fredericton, N.B., and I have listed the associates of this species found in red and white pine logging slash in western Quebec (Thomas, 1955). Leach, Orr and Christensen (1934) and Orr (1935) discussed the association of this bark beetle wit11 blue-staining fungi in red pine logs in Minnesota. Most of the observations reported in this paper concern the life history of I. pini in jack pine at Black Sturgeon Lake in northwestern Ontario from 1952 to 1960. Supplementary observations were also made on the seasonal development of this insect in red pine in southern Ontario in 1956 and 1957, and in white pine at Laniel, Quebec, in 1951.

Recent papers by Watt (1959) and Holling (1959) have renewed interest in the use of mathematical formulae as tools in the study of population dynamics. But the usefulness of mathematical formulae can be no greater than the accuracy of the data that are fed into them and at present accurate methods of estimating insect populations are generally lacking.

Estimates made by the method of marking release and recapture, described by Lincoln (1930) and improved by later authors, depend for their accuracy on the thorough mixing of marked individuals in the wild population. The method was used by Richards (1953) to measure populations of the red locust in Tanganyika, and the purpose of the present investigation was to determine its suitability in estimating populations of the migratory grasshopper, Melanoplus bilituratus (Walker).

Some information of interest on the postdiapause development of the larch sawfly, Pristiphora erichsonii (Htg.), and its tachinid parasite Bessa harveyi (Tnsd.) has been obtained in the course of laboratory rearings. Sawfly cocoons were placed in cold storage at 2 to 3°C. in September or October and held until the following year, usually late March, when they were incubated at 10 or 15°C. They were then held at constant temperatures until emergence was complete. Sawfly and parasite emergence was recorded daily.

Extensive trials showed that a nematode of the family Neoaplectanidae and its associated bacterium did not act as a permanent or temporary biological control agent against the Colorado potato beetle, Leptinotarsa decemlineata (Say). These trials and the causes of the failure were investigated for a number of years at Belleville; the initial test was reported by Welch (1958). The nematode, commonly known as DD 136, was discovered in codling moth larvae by Dutky and Hough (1955). It is ingested with food by the host, passes through the gut wall into he haemocoele, and releases a bacterium that multiplies rapidly and kills the host. The nematode feelds on the body contents of the dead host, passes through several generations, and eventually leaves the host as an infective larva. Dutky, and we, found that many kinds of insects can be infected by the nematode in the laboratory. It may be reared in large numbers by infecting larvae of the greater wax moth, Galleria mellonella (L.). The larvae die within 36 hours at room temperature and are then placed on wet filter papers in a trap designed to recover the nematodes that emerge from the dead hosts. Storage of the nematodes in water at 45° F. for a month or more causes no decrease in vitality or infectivity, so that large numbers may be accumulated for field trials. These sturdy animals may be applied with a mechanical sprayer at pressures of 100 psi without injury.