Head transverse, as broad as thorax; eyes prominent, not hairy; occipital carina absent; antennae far apart near top of eyes; upper face (“frons”) very short, nearly horizontal; lower face flattened and broad (Figs. 3, 4); antennae 21- to 23-jointed.

Notaulices present, extending almost to centre of mesonotum but remote from one another; prepectal carina absent; mesopleural furrow long and horizontal.

This paper describes the seasonal history and habits of three borers of the genus Dioryctria that destroy red pine cones in Ontario. These insects, as a group, generally rank second in importance as cone destroyers to the cone beetle, Conophthorus resinosae Hopk., which was the subject of the first paper in this series (11), and are presented together because of their family relationship and the similarity of their habits.

The genus Hystrichopsylla is Holarctic in distribution; its species include the largest known fleas. Only a few of the species exhibit marked host preferences. H. talpae (Curtis), the type of the genus, occurs through much of Europe and Asia, where the favoured hosts are insectivores and small rodents. It differs from all other known species chiefly in the presence of true combs of long, pigmented spines on abdominal terga II to IV (Fig. 1). Because of the differences, Ioff and Scalon (1950, in Ioff and Scalon et al., p. 273) proposed the subgenus Hystroceras (type, H. satunini Wagn.) to contain a group of Palaearctic species (satunini Wagn., microti Scalon, and nicolai Scalon) that have the abdominal combs reduced to series of apical spinelets (Fig. 2); this taxon would include all the known Nearctic species of Hystrichopsylla. Ioff and Scalon considered Typhloceras Wagn., known only from the Palaearctic region, a third subgenus, but this interpretation will probably not be generally followed.

When Wyatt and Kalf (in press) reported the presence of glycerol in the haemolymph of Hyalophora cecropia (L.) pupae, the possibility that it was responsible for the ability of this stage to survive freezing was naturally raised. It is well known that glycerol may protect animal tissues from injuries otherwise caused by ice formation. Many other substances have a degree of similar protective ability but are less effective for various reasons. Lovelock (1954) tested the protective action of 15 neutral solutes on human red blood cells and found glycerol to be almost ideal because of its high solubility in aqueous salt solutions, its ability to permeate the cell rapidly and completely, its low molecular weight, and its absence of toxicity even when in great excess.

Vol. LXXXVIII; p. 685: the caption under Figure 2 refers to the cut above Figure 3; the caption under Figure 3 refers to the cut above Figure 2.

Discrepancies in the degree of biological control of insect pests where the food plant species of the host were the only known variants in the environment have been subjects of scattered observations in the literature by Morgan (1910), Compere (1936), Gilmore (I938), and others.

A long period of speculation on the existence of strains of California red scale, Aonidiella aurantii (Mask.) immune to attack by parasites culminated in the discovery by Flanders (1939a, 1942a) that the hymenopterous parasite Habrolepis rouxi comp. reproduced satisfactorily on A. aurantii on Citrus spp. but that verv few emerged from the same species of scale on sago palm, Cycas revoluta Thunb. This was considered to be the reason for Compere's early failure to bring the hymenopterous parasite, Comperiella bifasciata How, from the Orient to California on scale-infested sago palm; Smith (1942) concluded: “Recognition must be given to the possibility that the host plant may confer on the host insect a kind of immunity to parasitization”.

On February 13, 1955, a collection of galls was taken from a row of willow shrubs, Salix sp., growing in a ditch on the west side of Adelaide Street between the sixth and seventh Concession lines of London Township, Middlesex County, Ontario. The galls ranged in size from about one inch to one and a half inches long and were fusiform in shape with a slightly curved beak at the tip (Fig. 1, 2, 3). They were identified, with keys and descriptions of galls of willow in Felt (1912, 1940), as beaked willow gills caused by the fly Phytophaga rigidae (O.S.). Several galls were split open, disclosing in each a narrow central chamher which was closed at its lower end and which opened at its upper end through the beak. In the chamber was an orange larvae, about 7 mm. long, with its anterior end toward the opening of the chamber. It was recognizable as an itonidid larva because of the presence on it of the “breast-plate” typical of larvae of the family Itonididae.

The technic of artificial insemination of insects offers a possible method for initiating or maintaining colonies of species which do not mate under laboratory conditions, and thus it may be possible to obtain a better understanding of their biology and permit the study of certain disease vectors. The technic might be applied to the study of the heredity of some species; it could be an aid to the taxonomist in the determination of species of questionable category.

Surveys of parasites of species of Hylemya that attack cruciferous crops were made in Canada as part of a biological control program against these insects. The most important species are Hylemya brassicae (Bouché), H. floralis (Fall.), and H. planipalpis (Stein.). Though not of primary importance on crucifers, H. cilicrura (Rond.) was often associated with the other species. The geographical distributions of these species in Canada were described by Brooks (1951).

Predacious mites of agricultural and horticultural importance are almost entirely of the family Phytoseiidae Berlese, 1913. These mites have received considerable attention both biologically and systematically in recent years, since the discovery that they feed on phytophagous mites of the family Tetranychidae that are of economic importance in many parts of the world.

Nesbitt (1951) revised the family in part, and present knowledge of the Phytoseiidae is largely based on his work. Garrnan (1948) devised a system of chaetotactic nomenclature that was used by both Nesbitt (loc. cit.) and Evans (1952) and is followed in this paper.

Work undertaken in connection with Mr. C. P. Kimball's projected list of Florida Lepidopera has revealed a number of problems in the North American species usually referred to Diasemia Hübner ([1824-25] p. 348), type Pyralis literalis Denis and Schiffermüller (=Phalaena litterata Scopoli) (Figs. 1, 2). A structural study shows that these species belong to five groups, generically distinct from one another and from the type species of Diasemia. Diasemia alaskalis Gibson (Fig. 3) is congeneric with Udea ferrugalis (Hübner) and should be known as Udea alaskalis (Gibson), new combination. I have characterized the genus Udea Guenée in an earlier paper (Munroe, 1950). Diasemia plumbosignalis Fernald (Fig. 10) and related species belong to the genus Choristostigma Warren, 1892: 440. The species of Choristostigma will be discussed in a separate publication. Diasemia magdalena Fernald and an undescribed species belong to the genus Daulia Walker (1859: 975) hitherto known from the tropics of the Old World and from Argentina. Hydrocampa ramburialis Duponchel and Desmia? janassialis Walker require new genera.

On October 16, 1956, during a routine monthly check of the Nurses Residence, Selkirk Mental Hospital, Selkirk, Manitoba, a professional exterminator noticed “thousands” of very small insects in a basement office. A number were submitted to the writer for identification and found to be aphids, which were later very kindly identified by W. R. Richards, Insect Systematics and Biological Control Unit, Ottawa, as Sipha agropyrella (H.R.L.). Richards stated (in litt.): “This is the first record of this species west of Ontario.” MacGillivray (1956) records the finding of this species in 1950 in New Brunswick as a new record for North America.

Neoleucopis pinicola Mall. is a common predator on the pine bark aphid, Pineus strobi (Htg.) in New Brunswick. The host adelgid occurs throughout most of the United States and southern Canada on white pine, Pinus strobus, L., Scots pine, Pinus sylvestris L., and Austrian pine, Pinus nigra Arnold (Craighead, 1950). It is also an occasional predator on the balsam woolly aphid, Adelges piceae (Ratz.) (Brown and Clark, 1956b). No reference to N. pinicola was found in the literature other than Malloch's (1921) description.

Generally throughout eastern Canada, wood borers of the genus Monochamus present the greatest single theat to softwood logs that must remain in the woods thrnughoat the summer and to standing trees killed as a result of fire or other disturbance. Althoush a considerable body of literature has been accumulated on the general biology and taxonomy of rlie econonucally important species (4, 5, 11, 15), on the ainount of damage caused by them under particular circumstances (2, 12), and on the protection of logs from damage (1, 3, 10, 13, 14), comparatively little detail is available on their seasonal development.

Cases of furuncular myiasis in humans have been reported in the literature from time to time, many of them having been attributed to parasitism by sarcophagid flies. O'Rourke (10) described a case of furuncular myiasis due to Wohlfahrtia vigil (Walk.) in a month-old infant at Ottawa. He reviewed the life-history and distribution of the species and previous records of myiasis cawed by it. Israels and Shuman (4) published an informative general review of myiasis dermatosa. Hunt and Edwards (3) reported a case in a three-month-old infanr at Montreal. This is a report on similar cases that occurred at Lethbridge, Alberta, in 1953 and in 1955 and a review of other records for Western Canada and the United States.

The most important predators found with broods of Ips pini (Say) and Ips perroti Sw. belong to the orders Coleoptera, Diptera, Hemiptera, and Acarina.

Among the Coleoptera, Enoclerus sphegeus Fab. was the most aggressive and responsible for the greatest predation. The small clerid, Thanasimus undulatus Say, was present in the area but rarely encountered. Dipterous predators included Loachea corticis Taylor, Oscinella sp. nr. magnipalpus Beck. and Medeterus modestus Van Duzee. A hemipterous egg predator, Anthocoris musculus Fall. was found occasionally within the main Ips galleries.

The most important factor affecting the densities of pollinating species of bees on alfalfa seed fields in southern Alberta is competing flowering growth (Hobbs and Lilly, 1954, 1955). This is a report on the relative attractiveness of red clover and alfalfa to honey, bumble, and leaf-cutter bees in southern Alberta. Observations were made on the first crops grown in each of two newly cultivated and irrigated areas near Hays; the fields were isolated from all other entomophilous crops by at least five miles of virgin prairie. A third series of observations was made on crops grown in the isolated river valley near Lethbridge previously described by Hobbs and Lilly (1955).

Studies on the biology and control of biting flies in the Canadian north have been described by Hocking et al. (1950), Twinn et al. (1948), and Twinn (1950). The biological investigations have been directed largely toward the economic control of biting flies in isolated military areas. In the subarctic regions of North America so many factors influence the rate of development of mosquitoes that simple relations of time and temperature cannot be used to estimate adequately the periods of infestation. Casual field observations of mosquito larvae and pupae suggested that behaviour patterns peculiar to northern species modify the effect of environmental conditions on the rate of development.

Since 1945, the European red mite, Metatetranychus ulmi (Koch) [=Paratetranychus pilosus (C. & F.)], has been one of the major pests in apple orchards in southwestern Quebec. Though it had been noted by Petch on fruit trees at Ville LaSalle, Que., in 1930 and at Lac Mégantic, Que., in 1931 it was not reported as causing serious injury to apple trees before July of 1945, when Beaulieu (1948) reported that it was responsible for the first important damage in a few orchards at Rougemont, Que. By 1946, infestations were general in the apple growing areas of southwestern Quebec and occurred as far east as the Quebec City district.

This paper describes the main anatomical features of the adult nervous system of the Douglas fir beetle, Dendroctonus pseudotsugae Hopk. The study on which it is based was carried out to provide a background for further work on the nervous system and as part of a program of investigation of the physiology and behaviour of scolytid beetles.

Extensive comparative studies of coleopterous nervous system were made long ago by Blanchard (1846) and Brand (1879). Their descriptions of scolytid material are sketchy and brief, however, and because we can find no other treatment of the nervous system in the Scolytidae we are presenting this brief report on our work.