During the summer of 1947, the potato inspectors (Dominion Division of Plant Protection) working in New Brunswick and Nova Scotia were given a course in potato aphid identification based on the methods presented herewith. In nearly all cases a high degree of accuracy was achieved in a few hours of practice. The purpose of this course was to aid the inspectors in determining the potential number of leaf roll vectors present. This paper is given with the hope that the method may be of value to others similarly interested.

The author published recently a “Revision of the Genus Nysius in the United States and Canada.” In compiling the data pertaining to the distribution of the species in Canada much assistance was rendered by three entomologists: Mr. G. Stuart Walley, Entomologist of the Department ot the Department of Agriculture, Ottawa; Mr. George A. Moore of Montreal, Que. and Mr. J. F. Brimley of Wellington, Ont.

In 1935, De Leon published a comprehensive paper on Medetera aldrichii as a predator ol Dendroctonus monticolae Hopk., in western white pine and lodgepole pine in Washington. The following data may prove of value because a different species of bark-beetle is involved and additional information is given. The observations were made in 1941 and 1942 at the Trinity Valley Forest Insect Field Station, 22 miles from Vernon. This locality is 2,100 feet above sea level in a mixed timber stand of western larch, Douglas fir, western red cedar, Engelmann spruce, western hemlock, and western white pine. D. pseudotsugae breeds in Douglas fir, and occasionally in western larch.