HYMENOPTEEOUS PARASITES OF ALEXIA. Ill 



"August 20, on the under side of a lower leaf (cotton), I found 

 two dipterous maggots, each about three lines long and apparently 

 identical with those found eating the pupa of Aletia. On this leaf 

 were no other living objects, except a few minute Aphids. The mag- 

 gots were busily exploring the surface of the leaf, raking it with their 

 jaw-hooks, but without cutting the epidermis. To one of the maggots I 

 gave the crushed body of a hemipteron, upon which it fed for a short 

 time only. I then gave it one-half of the body of a caterpillar, which 

 it immediately entered from the ruptured end and began feeding rav- 

 enously. The other maggot I placed upon the body of a liviug cater- 

 pillar. It at once took hold with its hook and began to twist its body 

 round and round like a gimlet. The caterpillar winced several times, 

 and five minutes later it plucked the maggot off with its jaws and 

 jerked it to such a distance that it fell clear off the leaf and upon the 

 ground. The maggot appeared to be injured, and afterwards refused to 

 take hold when replaced upon the caterpillar. The other maggot was 

 placed upon the body of a liviug caterpillar, but was thrown off again 

 without securing a hold. I afterwards killed a caterpillar by pinching, 

 without rupturing its head, but this the maggot refused to bore into. 

 These maggots were afterwards fed upon Aletia pupse, which at first I 

 had to crush for them. When nearly full grown, having been accidentally 

 overlooked and ill supplied with food, 1 found each in the act of eating 

 the other, and, of course, both died." 



Issuing from the Chrysalis. — The foregoing species issue in the larva or 

 maggot state mostly from the worm, and usually undergo their trans- 

 formations independently of their host. All the other parasites yet to 

 be mentioned undergo their transformations within the chrysalis and 

 gnaw their way out of the more or less completely emptied shell as per- 

 fect insects. The Aletia is attacked, however, in the larva state, the 

 parent parasite stinging and laying her eggs beneath the skin of the 

 worm, the parasitic larvae affecting the vital parts only after the trans- 

 formation of the victim to the chrysalis state. 



The Watchful Pimpla. — This species {Plmpla conquisitor, Say ^^) 

 sometimes destroys from 15 to 20 per cent, of the last brood of Aletia, 

 and the chrysalides that are whole and that appear sound or alive 

 after a good frost are found to contain its larva or pupa in still greater 

 proportion. It has been obtained from Aletia from all parts of the South, 

 and by most of the observers and agents of the Commission, the fly issu- 

 ing sometimes in thefall, but mostly in spring. It is a black, four- winged 

 fly, varying in length from one-fourth to one-half of an inch, and may be 

 distinguished from other native species of the genus Pimpla by having 

 the margins of the abdominal segments white. The exserted ovipositor 

 does not exceed one-half the length of the abdomen, and the male may 

 be recognized by the absence of an ovipositor and by his more slender 

 body. Say reared the species from a follicle of a case-bearing Bombycid 

 moth with transparent wings, probably the common Bag Worm ( lliyri' 



