NATURAL ENEMIES. 



A number of parasitic insects attack and kill, the catalpa sphinx. 

 Apantcle* congregates Say. a common, widespread, and very gen- 

 erally parasitic enemy of sphinx caterpillars, attacks this species 

 quite as freely as it does the " horn worms " of tobacco and tomato. 

 Unfortunately this parasite is in turn parasitized by other Hyme- 

 noptera, of which two species, Mesochorus aprilinus Ashm. and H&mi- 

 teles mesochoridis Eiley MS., are recorded. These secondary para- 

 sites in our experience, however, are not generally abundant ; hence 

 the beneficial primary parasite flourishes in spite of their attack. 

 Apantelt s congregaius, the primary parasite, is a minute, four-winged, 

 wasplike fry. Its larva, a white, maggotlike creature, develops 

 within the body of the caterpillar, and when full fed and ready for 

 transformation each indi- 

 vidual eats a hole through 

 the skin of the caterpillar 

 and spins its little white 

 cocoon on the outside. Two 

 hundred or more of such 

 cocoons may be seen on the 

 body of a single caterpillar. 

 After a few days the 

 winged parasite issues from 

 the cocoons to lay eggs and 

 produce another generation 

 of larva?. This parasite is 

 abundant throughout the 

 eastern United States. 



Micro [>h 'tis ( ApanteJes) 

 catalpa Riley, which ap- 

 pears to be a special parasite of the genus Ceratomia, is also recorded 

 as an enemy of the species under discussion. Extensive parasitism of 

 the catalpa sphinx by this species was observed by Mr. A. F. Burgess 

 at Jackson, Ohio, in 1905. In one case a large number of the hyper- 

 parasite Ftypopteromalus tabacum Fitch and a few individuals of 

 Horismenus (Holcopelte) microgastri Ashm. were reared from the 

 same lot of larva 1 , the hyperparasites outnumbering the primary 

 parasites four to one. This, however, is exceptional. 



Two common species of tachina fiie>. Euphorocera claHpennis 

 Macq. (fig. 2) and Frontina frenchii Will., also attack the larva of 

 the catalpa sphinx. These are general parasites of Lepidoptera, the 

 former infesting 27 distinct species, the latter 22; 



I (ir. 96] 



Fig. 2. — Euphorocera claripennis, a parasite of the 

 catalpa sphinx : Adult with puparium at right 



and enlarged antenna at left. (From Howard.) 



