298 HYMENOPTERA. 



differs from the typical forms in having the recurrent nervure interstitial ; but as our 

 insect agrees in other respects, I think we must provisionally regard it as belonging to 

 Wesmael's genus, which contains but few known species. 



1. Heteropelma sonorensis. (Tab. XII. fig. 30.) 



Niger ; facie, orbitis, scutello, pedibus 4 anterioribus, pedibus posticis pro parte tegulisque, flavis ; antennis 



runs. 2 - 

 Long. 17 millim. 



Hab. Mexico, Northern Sonora {Morrison). 



Antennae not much longer than the head and thorax united, stout, 33-jointed, covered 

 with a depressed pile ; the third joint not much shorter than the three following ones 

 united. Head covered with longish white hair, strongly punctured, coarsely rugosely 

 striated below the ocelli. Thorax covered with long white hair, which is especially long 

 on the sides and breast, strongly punctured all over ; metathorax rugose, reticulated in 

 the middle and at the sides behind, where there are two not very distinct keels ; the 

 keels in front of the scutellum are acute and curved, and they are prolonged forwards 

 along the tegular ; scutellum raised, broader than long, narrowed behind. Abdomen 

 about twice the length of the thorax ; the first segment cylindrical, a little longer than 

 the second, the latter dilated towards the apex ; the first two segments, and the others on 

 the top and the lower edge of the sides, are ferruginous, stained with black ; there is a 

 long black line on the second and on the fourth and fifth segments ; the sides from the 

 third segment, the ventral surface, and the sheaths of the ovipositor are yellow. The 

 four anterior legs are entirely bright yellow ; the posterior legs have the coxae black ; 

 the basal joint of the trochanter, the femora, the apical third of the metatarsus, and the 

 other tarsal joints dark rufous; the apical joint of the trochanters, the basal two thirds 

 of the tibiae, and the basal two thirds of the metatarsus, yellow ; the apical third of the 

 tibiae, and a spot on the apex of the metatarsus, black. Wings smoky, with a violet 

 tinge, the costa and stigma testaceous ; the recurrent nervure is interstitial. 



EXOCHILUM. 



Exochilum, Wesmael, Bull. Acad. Brux. xvi. p. 121 (1849). 



A genus containing but few species, and not yet found in America south of Mexico. 

 It is also represented in Europe. 



1. Exochilum mundum. 



Ophion mundus, Say, Bost. Journ. Nat. Hist. i. p. 239 ($) 1 ; Lee. Complete Writings of Thomas 



Say, ii. p. 695. 

 Exochilum mundum, Cresson, Proc. Acad. Phil. 1873, p. 375 i . 

 Campoplex flavipes, Brulle, Hist. Nat. Ins. Hymen, iv. p. 170. 



Hab. North America, United States \ — Mexico, Cordova 2 . 



