In the Northern Insect Survey, sponsored jointly by the Canada Department of Agriculture and the Department of National Defence, the insect fauna of northern Canada was investigated extensively during the summers of 1947-52. The research work has centred on the biting flies and has consisted in large part of taxonomic studies, as a preliminary to biologica1 investigations. In mosquitoes of the genus Aedes, the difficulty of identifying the adult females, particularly those of the black-legged groups, has made biological studies extremely difficult.

In the Ottawa region about the middle of June, frequently certain leaves of the common alder, Alnus rugosa var. americana (Regel) Fern., are drawn together by strands of silk, concealing an elongate silken tube or case. The latter is occupied by an active brownish-grey larva that, when unmolested, extends itself from the broadly open end of the rube to feed on the foliage. This insect is the phycitid Acrobasis rubrifasciella Pack., a species that occors in northeastern United States and adjacent parts of Canada.

This paper presents the results of bioclimatic investigations of two species of diprionid sawflies, Neodiprion americanus banksianae Roh. and N. lecontei (Fitch), important defoliators of pines in eastern North America. It deals primarily with the reactions of larvae of both species to gradients of evaporation rate.

Ixodes signatus Birula, 1895, pp. 357-358, Pl. 1, Figs. 10-13.

Ixodes arcticus Osborn, 1899, p. 553. Synonym, fide Cooley and Kohls, 1945, p. 201.

Ixodes parvirostris Neumann, 1901, p. 284. Synonym, fide Banks, 1908, p. 21, and Nuttall et al., 1911, p. 261.

Ixodes eudyptidis var. signata [Birula], Neumann, 1904, p. 451. Synonym, fide Nuttall et al., 1911, p. 261.

Ceratixodes signatus (Birula), Banks, 1908, p. 21, Pl. II, Figs. 1-3.

In certain years, adult sawflies constitute a conspicuous feature of the insect fauna which rests on foliage or visits flowers on the Canadian prairies and in neighbouring woodlands.

The most intense “outbreak” of these insects observed by the writer occurred in 1929 when they were by far the most conspicuous representatives of the insect fauna near Gull Lake, Alberta. In that year, in less than two weeks during early June, 53 species were taken in an area of about a half-mile square.

Until 1951 the Canadian National Collection of Insects lacked specimens of the barberry geometrid, Coryphista meadi (Packard), from Eastern Canada. In that year Mr. W. E. Whitehead, Macdonald College, Que., forwarded for identification two specimens taken in Kings County, N.S., and on learning of the interest of the record he kindly presented them to the National Collection. In 1952 an outbreak of the species in the Ottawa region caused minor damage to ornamental barberry bushes. Several enquiries about the insect were received, and MacKay (in preparation) studied its life-history.

Eight larvae of the new subspecies Coryphista meadi atlantica Munroe, the barberry geometrid, were reared from eggs. Hatched eggs, first-instar larvae, head capsules of the various instars, one last-instar skin, and seven last-instar larvae were preserved for the present study. The head capsules indicated only four instars. The female adults were identified by Dr. E. G. Munroe, Systematic Entomology Unit, Entomology Division.