26o 



The Journal of Heredity 



THE SHRIVELLED CATERPILLARS ARE ABANDONED BY THE FULL GROWN MAGGOTS 



By the time the maggots become full grown the caterpillars are reduced to shrivelled rem- 

 nants. The maggots then spin white silken cocoons in which they pupate. Note also the illustra- 

 tion below which shows a cocoon farther advanced in growth and the caterpillar more shrivelled 

 (x4i^) (Fig. 18.) 



VIEW OF COCOON AND SHRIVELLED 

 CATERPILLAR (Fig. 19; 



ten days. The wasps do well under 

 conditions considerably more arid than 

 the moths can endure. Doten (1911, 

 Agricultural Experiment Station, The 

 University of Nevada. Technical 

 Bulletin No. 78) states that Hadro- 

 hracon is able to survive lack of mois- 

 ture better than any other H\menopter 

 with which he experimented. The 

 females sling the caterpillars and suck 

 juice from the puncture. Males obtain 

 no nutriment in this way and will live 

 only a few days at room temperature 

 imless they be fed. Either males or 

 females may be kept alive in shell 

 \ials for extended periods by feeding on 

 a mixture of honey and water. It has 

 been found con\'enient when a few 

 insects are being kept for mating pur- 

 poses, to haxe a small bottle of honey 

 and a little water in a separate con- 

 tainer, for if the two be mixed fermen- 

 tation occurs. A metal rod such as a 

 line knitting needle is dipped into the 

 honey, then into the water and touched 

 to the inside of the vial where the drop 

 will adhere. If the insect be hungry 



