MESOSTENUS. 221 



of the apex of the metanotum, covering the similarly-coloured spines, yellow. Petiole 

 and postpetiole shining, impunctate, the apex of the latter broadly yellow. The re- 

 mainder of the abdomen aciculate, each segment banded with yellow at the apex. Sheath 

 of the ovipositor stout, broad. Areolet small, narrow, nearly double as long as wide. 



19. Mesostenus montezuma* 



Long. 19 millim. 



Hdb. Mexico, Orizaba (Bilimelc). 



A species identical, in the coloration of the head, thorax, and abdomen, with M. fra~ 

 ternans, but of a stouter build, the thorax especially being broader ; differing otherwise 

 from that species in the legs being yellow (not fulvous), except the hind femora ; in the 

 four anterior femora being lined behind with black, and the posterior femora above and 

 halfway down the sides black ; in all the coxae being black at the base, and the hinder 

 pair bearing a broad black stripe down the centre on the outside, and a large, broader, 

 and shorter mark on the inner side ; the trochanters being also marked with black, 

 especially at the base ; and the apices of all the tarsi black. 



20. Mesostenus modicus. 



Mesostenus modicus, Cresson, Proc. Acad. Phil. 1873, p. 154 ( ? ) \ 

 Hob. Mexico, Cordova l (Swnichrast). 



21.. Mesostenus communis. 



Mesostenus communis, Cresson, Proc. Acad. Phil. 1873, p. 154 ($ ? )\ 

 Hob. Mexico, Cordova, Orizaba x (Sumichrast), Mirador 1 (Dr. Sartorius). 



%tt Mesostenus ornatifrons. (Tab. X. fig. 17.) 



Niger, capite flavo-maculatus ; linea pronoti, scutello, segmentisque abdominis apice, flavis ; pleuris, metatho- 



race pedibusque, fulvis ; alis hyalinis. $ . 

 Long. 13 millim. ; terebra 4-5 millim. 



Hdb. Mexico (SalU) ; Costa Eica, Irazu (Rogers) % 



Antennae, if anything, longer than the body, thickened towards the apex ; the yellow 

 ring on the flagellum broad. Head punctured, the orbits, a triangular mark below the 

 antennae, the labrum, and a larger mark on the clypeus, yellow. The antennae originate 

 from distinct tubercles, which are yellow. Thorax punctured, semiopaque above ; the 

 sides obscurely striated. The tegulse and the tubercle below them, the collar in front, 

 a line on the edge, the anterior part of the mesopleurae, the scutellum, and the post- 

 scutellum, yellow. . Scutellum longer than broad, narrowed towards the apex. The 

 metanotum is blacK t ^Lin^ the transverse keel ; upfront <fi it and the pleurae fulvous, 

 as are also the sides of the mesothorax. The metanotum behind t he carina is opaque, 







