. Bulletin of the Department of Agriculture. Agriculture. Fig. 11.—Pteromalus eurymi: Larva. Greatly enlarged. (Original.) Fig. 12.—Pteromalus eurymi: Pupa. Greatly enlarged. (Original.) B'IG. 13.—Pteromalus eurymi: Adults is- suing from chrys- alis of alfalfa cat- erpillar. Enlarged nearly three diam- eters. (Original.) eggs are laid in pupae of Eurymus, from 40 to 114 parasites develop- ing in one pupa. About 80 to 90 per cent of these are females and the rest males, and the adults issue from one or more tiny holes in the pupa of their host. (See fig. 13.) The combined length of the egg
. Bulletin of the Department of Agriculture. Agriculture. Fig. 11.—Pteromalus eurymi: Larva. Greatly enlarged. (Original.) Fig. 12.—Pteromalus eurymi: Pupa. Greatly enlarged. (Original.) B'IG. 13.—Pteromalus eurymi: Adults is- suing from chrys- alis of alfalfa cat- erpillar. Enlarged nearly three diam- eters. (Original.) eggs are laid in pupae of Eurymus, from 40 to 114 parasites develop- ing in one pupa. About 80 to 90 per cent of these are females and the rest males, and the adults issue from one or more tiny holes in the pupa of their host. (See fig. 13.) The combined length of the egg, larval, and pupal stages in the warmer weather of August is from 12 to 15 days, while the pupal stage was found to cover 4 days in the month of August and 12 to 15 days in February, the variation being due to differences of temperature. Thus several generations are possible each season, and thus, with abundant egg production and high percentage of females, gives rise to a rapid increase in the number of parasites, so that by late August the multiplication of the host species is Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States. Dept. of Agriculture. [Washington, D. C. ?] : The Department : Supt. of Docs. , Govt. Print. Off.
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