Hot spots may develop quickly in farm stored grain under Canadian winter conditions. Heavy infestations of mites, insects and fungi may accompany such hot spots (Stirrett and Arnott, 1933; Watters, 1955). Once the heating process is initiated, whatever its cause, it brings about a rapid deterioration of grain, tluough charring of kernels, and reduction of their germinability, and by providing optimum conditions for the growth and reproduction of storage fungi, insects and mites.

The two new genera and species described in this paper can be distinguished from other rose-infesting aphids in North America by means of the key given below. Specimens of Macrosiphum nigromaculosum Macdougall were not available for examination and this species has been worked into the key on the basis of descriptions by Macdougall (1926) and Palmer (1952).

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.).

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).

The genus Bolbomyia Loew, 1850, was erected on the basis of specimens in Austrian amber. No specific name was applied to the material. Bolbomyia nana Loew was described in 1862 from a single female collected at Washington, D.C., U.S.A. The species has since been redescribed twice, as Misgomyia obscura by Coquillett, and as Ptiolina mitis by Curran, on the basis of eastern North American material.

A second species has recently been collected in western North America, and it is the purpose of this paper to describe this new species and redescribe the genus.

The two most important economic species of Elateridae in Saskatchewan are Ctenicera aeripennis destructor (Brown) and Hypolithus bicolor Esch. Adults of both species have been observed moving on the soil surface, but the extent and the seasonal duration of this movement has never been fully investigated.

The activity of several species of wireworm adults has been studied by trapping with baits, or by collection from underneath various types of cover where they seek refuge (Hawkins 1936, Campbell and Stone 1939 and Cohen 1942). This type of trap however, gives no assurance that the beetles will stay under the refuge for any definite period, and docs not permit a quantitative estimate nf the population.

Sterility of grasses caused by a constricted brown region, usually in the upper internode, is commonly described as silver top because of the bleached appearance of the inflorescence. Hodgkiss (1908) reported that silver top was caused by the mite, Siteroptes graminum (Reuter), in conjunction with the fungus, Fusarium poae (Pk.) Wr. Brown et al. (1952) found that in the greenhouse several chlorinated hydrocarbons controlled S. graminum. Hardison et al. (1957) reported that S. graminum in combination with F. poae was of little importance in causing silver top of cultivated grasses in western Oregon. They suggested that two thrips of the genus Aptinothrips might be the primary cause. They recommended DDT or heptachlor applied in late April or early May. They also found that post-harvest burning reduced silver top.

In the course of studles on different species of defoliators in field-spruce stands on the Gaspé coast of the Baie des Chaleurs, Griselda radicana (Wlshm.) occurred fairly commonly in such stands. Although the principal host tree of this insect is white spruce, Picea glauca (Moench) Voss, records of the Forest Insect and Disease Survey show that it has been collected from black spruce, Picea mariana (Mill.) BSP., Colorado spruce, Picea pungens Engelm., and balsam fir, Abies halramea (L.) Mill. Although G. radicana is commonly found across Canada, there are no records that it has ever reached outbreak proportions. These investigations were undertaken since nothing was known on the life history and habits of this insect. The studies were carried out near New Richmond in the Gaspé Peninsula in the summer of 1959.

In research on insect immunity, bacterial antigens were injected into Galleria mellonella L. larvae (Stephens, 1959). It was suspected that the quality and quantity of the blood, or hemolymph, might differ if the larvae were obtained from different sources. This note reports the effects of food and storage on the specific gravity and osmotic pressure of the blood, and of storage on the blood volume.

Eurytoma pini Bugbee (Bugbee, 1958), a common parasite of the European pine shoot moth, Rhyacionia buoliana (Schiff.), in Ontario, was previously recorded from this host as E. appendigaster (Swed.) (Coppel and Arthur, 1953) and as E. thylodermatis Ashm. (Miller, 1953). Bugbee (1958) recorded it from various lepidopterous hosts that mine in plant tissues. These include: the Nantucket pine tip moth, Rhyacionia frustrana (Comst.); the bagworm, Thyridopteryx ephemeraefomis (Haw.); the ragweed borer, Epiblema strenuana (Walkr.); the lima bean borer, Etiella sp.; the pink bollworm, Pectinophora gossypiella (Saund.); Acrobasis rubrifasciella Packard; and Eucosma scudderiana (Clemens). Bugbee stated that the range of E. pini probably includes all of the pine growing regions of North America.

The role of natural enemies in the control of the pear psylla, Psylla pyricola Foerst., has been of minor importance in the published history of this pest in North America. Jensen (1957) listed six species of parasites that attack the pear psylla nymph, but only one, Psylledontus insidiosus Cwfd. (Hymenoptera: Encyrtidae), is recorded from North America. Slingerland (1896) stated that the predators Chrysopa oculata Say (Neuroptera: Chrysopidae) and Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were observed in the field feeding on psyllid eggs, nymphs and adults. Georgalla (1957) reported that Anthocoris nemorum L. (Hemiptera: Anthocoridae) fed upon pear psylla eggs and nymphs, but made no reference to effect upon psyllid populations.

Two species that formerly were confused in the literature with Gerris rufoscutellatus Latreille are G. notabilis Drake and Hottes (1925) from western North America, and G. dissortis Drake and Harris (1930) from eastern North America. Drake and Harris (1934) concluded that Palaearctic rufoscutellatus did not occur in America.

The species described herewith as Gerris nearcticus n. sp. is similar to notabilis, dissortis and rufoscutellatus in general appearance and coloration. However, the males are readily separated from notabilis and dissortis by the prominent median keel on the first genital segment (Figs. 1, 2). Another Nearctic species with a similar median keel is G. conformis (Uhl.), but it has a very long first antennal segment, which is longer than segments two and three together. The first antennal segment of nearcticus is much shorter than segments two and three together.

It has long been known that life events occur earlier at lower than at higher altitudes (Hopkins, 1918; Chapman, 1931; Uvarov, 1931). Treherne and Buckell (1924) refer specifically to the earlier appearance of the clear-winged grasshopper, Camnula pellucida (Scudder), near Nicola Lake, B.C., (2020 ft.), as compared with its appearance at nearby but higher places such as Douglas Lake (2600 ft.) and in the areas between Minnie Lake and Aspen Grove “where the elevation at many points exceeds 3500 feet.” These references, and the possibility of using the knowledge to help determine dates when control operations may be necessary on various ranges in any one season, suggested the need for more precise measurements of the development of this major rangeland pest at different altitudes in different years.

In the spring of 1957, Mr. K. J. Crawford, Gananoque, Ontario, took some interesting photographs of some mosquitoes that were feeding on a frog. With Mr. Crawford's kind permission, we reproduce one of these photographs (Fig. 1). This photograph was taken among the reeds of a swampy depression a few miles north of Marnlora, Ontario. As it was taken early in the season, April 26 to be exact, the mosquitoes had probably overwintered as adults. They attacked the frog fiercely, but did not bother the photographer. The mosquitoes can not be identified with certainty from the photograph, but they probably belong either to the genus Culex or the genus Culiseta. The evidence suggests that they are Culex territans Walker. This species probably overwinters in the adult stage in Ontario, is a known amphibian feeder, and is not believed to attack man (Carpenter and LaCasse, 1955).

The design of orchard pest control programs that favor natural enemies is based partly on a knowledge of the toxicity of spray chemicals to beneficial arthropods. This paper summarizes the results of tests conducted during the past five years to determine toxicities, and it includes some previously published data (MacPhee and Sanford 1954 and 1956). Tests were discontinued after 1955 on the species Stethorus punctum (Lec.), Euderus spp., Scambus spp., and Trichograma minutum Riley and on the chemical formulations Aramite, Chlorocide, Erad, fixed nicotine, lime sulphur, Puratized Agricultural Spray, summer oil, and synthetic cryolite. Tests were initiated on the phytoseiids Typhlodromus finlandicus (Oudms.) and T. rhenanus (Oudms.), and the mirid Psallus sp., and also on the pesticides Bacillus thuringiensis Berliner preparation, demeton, Diazinon, dodine, Kelthane, Kepone, Rhothane, Sevin, Tedion, Trithion and zineb. Typhlodromus pyri Scheuten was previously reported as T. tiliae (Oudms.), a synonym, and Atractotomus mali (Meyer) is an authoritative identification of the species previously listed as Criocoris saliens (Reuter).

During the month of August, 1960, I had the opportunity of studying the extensive collection of ant-lions at the Museum of Comparative Zoology, Harvard University. This collection contains most of the type material of Nathan Ranks and Hermann Hagen. In many cases only syntypes were present which necessitated the desicgnation of lectotypes. Whenever possible I have selected and designated a male specimen as the lectotype since many of the specific characters are restricted to the males. Others of the syntypical series were labeled lectoparatypes. In many instances one specimen had a “type” label and the rest of the series “paratype” labels or no labels at all. However, these labels were not considered to be type designations as they were not indicated as such in the original descriptions. The specimens were therefore considered to be syntypes. Also, in checklng the specimens listed in the original descriptions with the available material, it was sometimes found that other specimens belonged to the type series, even though they were not so labeled. I have included such specimens in my decisions on lectotypes.

The stout, red-and-black adults of the milkweed beetle are common during June and July on the leaves and flowers of Asclepias spp. over most of the range of these plants. It has long been known that the larvae inhabit the soil, feeding on the roots of the host. Craighead (1923) found larval galleries extending from root to root in the soil, and upwrards to immediately below the soil surface, where pupation occurs. My own observations corrolborate Craighead's; larvae were found in the soil feeding on the outside of the milkweed roots. Thus the larvae are free-living, terricolous insects, much like white grubs.

In May, 1958, studies on the distribution of fruit, and of fruit damages from all sources; were initiated in permanent apple orchard plots at Rougemont, Que. The object was to develop sound sampling techniques to determine, within error limits, damages to the fruit resulting from the feeding activities of orchard insect pests, and from mechanical causes, during the period apple set in early June to harvest in mid September. This is a report on variation in samples of apples, and of damages to the fruit from all sources, for the years 1958 and 1959, and on sampling recommendations.

Most of the published references to Newfoundland caddisflies are derived from one early paper by Nathan Ranks in 1908. Several collections received recently, however, have considerably extended knowledge of the Newfoundland caddisfly fauna. As might be expected, many of the species occurring in Newfoundland also extend across the whole of northern North America, and to some extent southward along the montane areas in both east and west. Some of these also occur throughout the holarctic area. Some of the species are, however, confined to northeastern North America. There are no species of caddisflies now known which are confined to the island of Newfoundland.

Research was conducted on the biology of cereal and grass aphids in the Madison area during 1957-59 in connection with epidemiological investigations of the barley yellow dwarf virus (BYDV). It becomes of increasing importance to know more about these aphids as potential vectors of the virus. Information was needed on the taxonomy, biology and ecology of the vector population to better understand the complex interactions between vector and virus. Two methods were used to obtain data on the occurrence and abundance of aphids. The conventional method of studying aphid populations on host plants was supplemented with intensive research on air-borne aphids, using the yellow-pan water trap developed by Moericke (1951), and the wind trap described by Shands (1942). These traps are shown in Fig. 1. The species of aphids were identified according to keys of Palmer (1952). Names of genera as used in Europe have been indicated in parentheses. In the following report the various forms in the life cycle are referred to as fundatrices (on the winter host), fundatrigenae (produced by fundatrices, the alates of this generation migrate to summer hosts), virginoparae (both apterous and alate individuals on snmmer hosts), and gynoparae (alates migrate from summer hosts to winter hosts).