458 



PROCEEDINGS OF THE NATIONAL MUSEUM 



Larval Key 



1. Three prominent setae situated beneath each labial palp.. . Coelichneumon 

 Six prominent setae situated beneath each labial palp. . . . Protichneumon 



Tribe Trogini 



Figure 36b 



Species of Tragus and Macrojoppa are parasites of Papilionidae. 

 The rest of the genera attack Sphingidae. 



Tragus pennator (Fabricius) (fig. 36b) was examined. This species 

 differs from other Ichneumonines examined in that the hypostoma is 

 sharply bent. 



Subfamily Mesochorinae 



Figure 37 



All members of this subfamily are believed to be endoparasites and 

 secondary parasties. 



Mesochorus discitergus (Say) (fig. 37) and Mesochorus sp. were 

 examined. 



The larval characters of the specimens examined indicate an 

 isolated group. Those head sclerites present are lightly sclerotized; 

 the epistoma is unsclerotized; the pleurostoma is present; only the 

 median part of the hypostoma is sclerotized in Mesochorus, but the 

 entire hypostoma is sclerotized in Astiphromma strenuum (Holmgren) 



0-1 m 



Figure 37. — Mesochorinae, head sclerites: Mesochorus discitergus (Say). (Antenna not 

 visible on preparation; 2, spiracle; 3, skin.) 



