. Bulletin of the Department of Agriculture. Agriculture. THE POTATO TUBER MOTH. 41 The record of a shorter hfe cycle follows: 1913. September 15.—Tuber-moth larva parasitized by ITabrobracon johannsem. September 18.—Parasite larvae nearly mature. September 19.—Parasite larvae spinning cocoons. September 20.—Parasite larvae pupating. September 25.—4 parasite adults issued. September 26.—17 parasite adults issued. Life cycle 10 days at an average mean temperature of 78° F. CHELONUS SlIOSHONEAXORl M VIER.^ This parasite (fig. 29) has been consistently abundant every year from 1912 to the pr
. Bulletin of the Department of Agriculture. Agriculture. THE POTATO TUBER MOTH. 41 The record of a shorter hfe cycle follows: 1913. September 15.—Tuber-moth larva parasitized by ITabrobracon johannsem. September 18.—Parasite larvae nearly mature. September 19.—Parasite larvae spinning cocoons. September 20.—Parasite larvae pupating. September 25.—4 parasite adults issued. September 26.—17 parasite adults issued. Life cycle 10 days at an average mean temperature of 78° F. CHELONUS SlIOSHONEAXORl M VIER.^ This parasite (fig. 29) has been consistently abundant every year from 1912 to the present time. Efforts to rear it from the larvae and pupae of the tuber moth failed, and, at the sug- gestion of Dr. Howard, the insect was placed with eggs of the tuber moth. Oviposition (fig. 30) took place at once, the parasites usually feeding on the moisture which collected at the wound caused by the ovipositor. The eggs of the tuber moth hatched normally, and the yomig larvae at once burrowed into the tuber. Later the matm'e tuber-moth larvae began to leave the tuber and start their cocoons. Some of the larvae ap- peared restless and darkened spindles were noticeable in their bodies (fig. 31), quite similar to those in the case of Campoi^lex 'phthorimaeae. None of the larvae pupated, and soon the mature parasite larva (fig. 32) emerged and spun its white cocoon within the cocoon of its host. This parasite promises to be of value in controUing the tuber moth in the field. It apparently does not work in darkened bins. The life cycle is divided as follows: 1914. July 26.—Tuber-moth eggs parasitized by Chclonus shnshoneanorum. July 31.—Tuber-moth eggs hatched. August 16.—Chelonus larvae matiue. August 18.—Chelonus larvae pupating. August 26.—1 Chelonus adult issued. August 27.—3 Chelonus adults issued. August 28.—2 Chelonus adults issued. Life cycle 31 days at an average mean temperature of about 72° Please note that these images are extracted fr
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