. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE GRAIN" BUG. 29 in this instance. In a similar experiment started on August 17, 1915, the duration of the life cycle was 26 days. The comparatively short life cycle of T. ashmeadi enables the species to complete several generations each year and greatly in- creases its value as a parasite. PARASITES OF THE ADULT. Field collections made from various and widely separated localities during 1915 and 1916 demonstrated that in some fields nearly 25 per cent of the adults and last-instar nymphs were parasitized by the
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE GRAIN" BUG. 29 in this instance. In a similar experiment started on August 17, 1915, the duration of the life cycle was 26 days. The comparatively short life cycle of T. ashmeadi enables the species to complete several generations each year and greatly in- creases its value as a parasite. PARASITES OF THE ADULT. Field collections made from various and widely separated localities during 1915 and 1916 demonstrated that in some fields nearly 25 per cent of the adults and last-instar nymphs were parasitized by the tachinid fly GyTrmosoma Pig. 12.—Oymnosoma fuliginosa, a fly parasite of the grain-bug adult. Mucli enlarged. According to Morrill (5) the female of this species usually de- posits her eggs near the margin of the body on the ventral pro- thoracic region of the adults and fifth-instar nymphs. The manner in which the resulting larva enters the body of its host has not been observed. The body contents are consumed within a short time and the fully developed parasite larva makes an exit through the anal opening of its host and enters the ground for pupation. The period of pupation for 24 individuals reared during the summer of 1916 6 to 15 days, the average period being days. The parasitized insect retains its activity and powers of destruc- tiveness up to within a short time before the parasite is due to emerge. This characteristic detracts somewhat from the value of G. fuliginosa and renders it of less importance than the ^^g parasite. 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 Dept. : Supt. of Docs. , G. P. O.
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