Certain Host-Parasite Relationships Involving the Spruce Budworm1

During studies of the parasite complex of the spruce budworm in the Lake Nipigon region of northern Ontario from 1946 to 1950, data were obtained on certain host-parasite relationships. The data were derived from two sources: the rearing each year of periodic collections of spruce budworms, and the dissection of budworm larvae and pupae that were collected and preserved at 2-day intervals during June of 1948 and 1949. The particular features investigated were: the sex ratio of parasites and its possible relation to the sex of the host; and the effect of parasitism on the apparent sex, rate of development, and size of the host.