Water beetles from the Canadian Arctic available in museums often lack any specific ecological data. In consequence, I was pleased to receive for study the specimens collected by Dr. D. G. Frey and Mr. J. B. Stahl on Southampton Island (Northwest Territories) while they participated in an expedition sponsored by the Indiana Gear Works of Indianapolis, Mr. John Buehler, President. The beetles were collected during the period August 10 to 26, 1957, in connection with limnological studies and are accompanied bv detailed notes on the habitats and associated organisms. I am especially indebted to Dr. Frey for allowing me to use and paraphrase his personal notes on the expedition. Mr. H. B. Leech of the California Academy of Sciences has kindly checked the determinations.

A trap for flying insects that incorporates some of the principles described by Williams and Milne (1935) and Chamberlin and Lawson (1910) was constructed. It consists basically of two conical nets that rotate in a horizontal plane around a central axis that is driven by an electric motor through a series of pulleys. The efficiency of the trap is not affected by wind as an increased airflow through one net is balanced by a decreased airflow through the other. It is green in colour to blend with its surroundings. The trap (Fig. 1) is 5½ feet high at the centre. It has three main sections (Fig. 2): the framework, the drivillg mechanism, and the nets.

A nuclear polyhedrosis virus has been isolated from the spruce budworm, Choristoneura fumiferana (Clemens) (Bergold, 1949; Bird, 1949; Bergold, 1951; Bird and Whalen, 1954; Bird, 1959), but no similar virus has been recovered from the jack pine budworm, Choristoneura pinus Freeman. Since these two species are very closely related (Smith, 1953) it was of interest to determine if C. pinus is susceptible to the C. fumiferana virus.

Of the many species of fleas incriminated in plague transmission, the most notorious is the oriental rat flea, Xenopsylla cheopis (Rothsch.). This is due to its early discovery as a plague vector (Simond, 1898), its demonstrated superior ability to transmit the infection (Kartman and Prince, 1956), and its recognition as the principal vector of plague from rat to man. Holland (1949) regards its presence in any geographical area as a matter of concern.

This paper is one in a series on techniques for estimating populations of various stages of the larch sawfly (Ives, 1055; Ives and Prentice, 1958; Ives and Turnock, 1959) to provide's basis for the evaluation of mortality factors. The larch sawfly overwinters in a cocoon in the soil and adults emerge during the spring and summer (Turnock, 1960). This paper describes the methods and results of sampling adults as they emerge from the soil.

Larvae of Aletia oxygala luteopallens (Sm.) found on chicory (Cichorium intybus L.) in Quebec City in May, 1958, were infested with a nuclear polyhedrosis virus and with a microsporidian. Larvae suffering from polyhedrosis leave the interior of the stems, die, and remain hanging in a characteristic way “glued” to the exterior of stems. The diagnosis of the polyhedrosis virus was confirmed by Dr. G. H. Bergold at the Insect Pathology Research Institute at Sault Ste. Marie, Ontario, and that of the microsporidian by Dr. H. M. Thomson of the same Institute. Neither microorganism had ever been noticed before.

The micro-organisms that accur in insects may be pathogenic, nonpathogenic, supposedly or actually beneficial, or casual invaders. The literature on the various aspects of the subject has become extensive (Buchner, 1953; Fraenkel, 1952; Shrewsbury and Barson, 1954a, 1954b; Steinhaus, 1946, 1949).

Type.-Neofacydes sinensis n.sp.

Flagellum.—Female flagellum moderately long, lanceolate, widened beyond the middle and strongly attenuated at the apex; basal segments of the male flagellum cylindric, at the apes however obliquely cut and overlapping, becoming gradually more distinct nodose bevond the seventh segment.

Head.—Occiput hardly emarginate, sloping down steeply behind the ocelli and eyes; cheek profile strongly narrowed with straight outline; median field of the face well defined; clypeus normal with straight apical border; frons concave; mandibles normal with small teeth.

Thorax.—Mesoscutum moderately convex, a little longer than wide; scutellum pyramidal; propodeum as in Trogus Panzer, the area posteromedia wide, parallel-sided, the upper border arched; areae posteroexternae with strong lateral carinae.

Legs.—Relatively long and slender.

Abdomen.—Female abdomen oxypygous, similar in appearance to a Coelichneumon abdomen; surface of tergites 1-5 strongly aciculated, tergites 1-5 strongly separated, sometimes with sharp lateral edges, but not bulging laterally; postpetiolus with aciculate median field; gastrocoeli deep, transverse.

Three known species of scale insects belonging to the genus Matsucoccus occur on pine trees in northeastern North America: M. gallicolis Morr., on pitch pine, Pinus rigida Mill., and scrub pine, Pinus virginiana Mill. (Parr, 1939); M. resinosae Bean and Godwin on red pine, P. resinosa Ait. (Bean and Godwin, 1955); and M. macrocicatrices Richards on eastern white pine, P. strobus L. (Richards, 1960). This last species. in contrast with the others, is closely associated with the fungus Septobasidium pinicola Snell. From 1957 to 1959 personnel of the Forest Insect Laboratory, Sault Ste. Marie, and the Forest Biology Laboratory, Fredericton, collected some 500 specimens from 21 areas in Ontario and the Maritime Provinces. These collections, augmented by herbarium specimens provided by the Forest Pathology Laboratory, Maple, from five other areas in Ontario, not only the insect specimens necessary for the dercription of the species, but information on its biology and distribution.

This paper contains a description of a species of Leucopis Meigen, subgenus Leucopella Allalloch (1927), and a note on occurrence of the subgenus in the New World (previouslv known only from Africa). Also a key is given to all the known genera and subgenera of the Chamaemyiidae.

Although the live weights of the successive stages of some of the old world Acrididae are known (Bodenheimer, 1929; Key, 1936; Duarte, 1938; Husain, et al., 1946; Davey, 1954; Richards and Waloff, 1954), this information has been obtained only for Melanoplus bilituratus (Wlk.) among the grasshopper species of Western Canada (Smith, 1958). In addition to the establishment of growth curves, weight data are useful for computing the biomass of acridid fauna in any situation. As data accumulate to permit the development of a generalized relationship of food consumed to body weight, (e.g. Davey, 1954; Misra, 1956; Gangwere, 1958; Smith, 1958; Putnam, unpublished data), live weight could become a useful quantity for estimating the damage potential of any acridid population.

In an assessment of spider predation on insects, an arbitrarily delimited woodland community was examined to determine the species of spiders present and their abundance and distribution therein. Periodic samples were taken from September, 1954, to September, 1956.

Many experiments in entomology are evaluated by counts of the number of individuals in each unit of space or time. The original counts may be summarized in a frequency distribution showing the number of units containing 0, 1, 2, 3 … individuals of a given species. If a population is distributed over a number of units at random, the distribution of numbers per unit will approximate a Poisson series, the variance of the population being equal to its mean. Such distributions are rare in nature. Usually there is an excess of unoccupied units and of densely occupied units over Poisson expectation. This departure from randomness is attributable to contagion, where the presence of one insect in a unit increases the probability of others occurring in that unit. It results from the egg-laying habits of adult insects, gregariousness of feeding larvae, etc.

The results reported in this paper are part of a study of the biology and control of black flies in the forests of Eastern Canada conducted on the north shore of the St. Lawrence River, near Baie Comeau, Quebec, during 1954, 1955, and 1956. Reference to this study is made in a review by Peterson and Wolfe (1958). The identification and biology of the black flies of this region has been reported on by Wolfe and Peterson (1959) who also describe the topography of the region. The important feature of this rugged area is an abundance of fast-flowing streams which provide highly suitable environments for the development of black-fly populations.

According to one of the popular ecological theories, populations are self-governing systems, which maintain themselves in existence by utilizing “density-dependent factors”, whose effect becomes more intense as the population increases and less intense as it decreases. This theory is connected with a mathematical model developed by V. A. Bailey and A.J. Nicholson, 1935, to represent the results of the interaction of predator and prey populations. According to the theory, as expressed verbally, a disturbance of the conditions of stability – the “steady state” – produces oscillations which tend to re-establish the stable conctition. In fact, however, when numbers are inserted in the equations, the population values, at the end of one or more cycles – which increase in amplitude if there are more than one – fall below unity, which, on a common sense view may be considered to mean the extermination of the prey, followed by that of its predator or parasite.

It was of interest but no great concern when the finding of Musca autumnalis DeGeer in Nova Scotia was reported by Vockeroth (1953). Previously, M. domestica Linnaeus was thought to be the only species of the genus present in North America. Two previous reports of M. autumnalis as corvina (Walker, 1849, 1871) were thought to be misidentifications.

Matsucoccus is composed of species of scales that are completely restricted to species of Pinus L. Inclusive of the species described herein, nineteen species have been described, mostly from North America; but hitherto the genus has been unknown in Canada.

The Douglas-fir cone moth has been reported causing damage to cones and seeds of Douglas fir for a number of years; reports of seed loss range from light to almost 100 per cent. The insect occurs throughout the range of the host in British Columbia, the Pacific Coast States, and the Rocky Mountains.

Observations recorded here were made during 1957 and 1958 in the Cowichan Lake area of Vancouver Island, and 1959 in the interior of British Columbia.

The Diamond-back moth, Plutella maculipennis Curt., is a cosmopolitan pest of cabbage, cauliflower, radish, mustard and other cruciferous plants; according to Fletcher (1920) it is distributed throughout India, Burma and Ceylon. During a recent visit to Kashmir the authors found this pest doing considerable damage to cabbage in vegetable gardens on the outskirts of Srinagar, and this appears to be the first record of this pest from the area. From a small collection of the caterpillars made, the authors have reared out the tachinid fly, Voria ruralis Fall., and the ichneumonid, Horogenes sp. A single specimen of Itoplectis sp. was also reared out, but this is likely to be a secondary parasite. Thompson (1946) has listed only Angitia fenestralis Hlgr. as parasitizing this species in India. Mani (1940) refers to Brachymeria excarinata Gahan and B. plutellophaga Girault as having been reared from pupae of the pest at Coimbatore. A careful search in India may reveal the presence of more parasites of this universal and important pest and their introduction into other countries might be helpful in its control.

The oviposition behaviour of Neodiprion sawflies has been the subject of much investigation in recent years. The impetus for this interest seems to lie in the paper by Atwood and Peck (1943), in which it was suggested that the number and spacing of eggs on needles were a useful tool for the identification of memhers of this important group of conifer defoliators. Ghent (1955) has analysed the egg clusters of N. pratti banksianae Roh., and Ghent and Wallace (1958) have investigated the behaviour responsible for the pairing of eggs on adjacent jack pine (Pinus banksiana Lamb. ) needles by N. swainei Midd. More recently, Ghent (1959) has presented a study of the factors determining the spacing of eggs by the European pine sawfly, N. sertifer (Geoff.). Of these, the 1955 and 1959 papers, in addition to making valuable contributions to our understanding of the behaviour of adults, cast doubt on the usefulness of the number and spacing of eggs as identifying characters in these species.