. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 28 DEPAETMENT BULLETIN 779. NATURAL ENEMIES. PARASITES. During the course of the investigations in New Mexico one procto- trypid parasite, Telenomm ashmeadi Morrill, was reared from the eggs of Chlorochroa sayi, and two tachinid parasites, Gymnosoma fuliginosa Desv. and {Ocyptera) Ocypterodes euchenor Walk, were reared from the adults of the species. PARASITES OF THE Fig. 11.—Telenomus ashmeadi, an egg parasite of the grain bug. Greatly enlarged. (Morrill.) The egg parasite Telenomus ashmeadi (fig. 11) constitute
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 28 DEPAETMENT BULLETIN 779. NATURAL ENEMIES. PARASITES. During the course of the investigations in New Mexico one procto- trypid parasite, Telenomm ashmeadi Morrill, was reared from the eggs of Chlorochroa sayi, and two tachinid parasites, Gymnosoma fuliginosa Desv. and {Ocyptera) Ocypterodes euchenor Walk, were reared from the adults of the species. PARASITES OF THE Fig. 11.—Telenomus ashmeadi, an egg parasite of the grain bug. Greatly enlarged. (Morrill.) The egg parasite Telenomus ashmeadi (fig. 11) constitutes one of the most effective natural agents in the control of Chlorochroa sayi and is very widely distributed through- out the area infested by the pest. During the latter part of July and the early part of August, in 1915, adult parasites emerged from about 60 per cent of the eggs collected in badly infested fields. In many Qgg clusters a parasite emerged from each and every egg. In all instances under observation it has been noted that nymphs rarely hatch from an egg cluster when any of the individual eggs produce parasites. Upon dissection these unhatched eggs gen- erally are found to contain dead parasites or to be nearly devoid of contents, apparently the result of parasitism. It is evident from the foregoing that the percentage of eggs from which adult parasites emerge does not necessarily indicate the full total of parasitism in the field. | On July 27, 1916, a dozen reared parasites were confined in a glass vial with a freshly deposited egg cluster of C. sayi. Within two minutes the females began ovipositing. During this process the female stands on the two posterior pairs of legs with the body nearly vertical and inserts her short ovipositor into the egg, meanwhile bending the head and antennae forward. They prefer to oviposit in the top of the egg or in the side of the egg near its top. On August 13 the adult parasites began emerging from this egg cluster, a total of
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