74 HYMENOPTERA OF AMERICA. [PART I. 



rufous. Wings cloudy, iridescent ; nerves and stigma blackish; 

 2d cubital cell as in E. regulus, as lung as wide; its radial 

 margin broad 



I'm-, a. Mandibles more ferruginous. Antennae dull ferrugi- 

 nous with an obscure line on the scape, and blackish on the 

 Qagellum. 



U. Head black without ferruginous spots. 



c. Prothorax ferruginous. 



d. Post-scutel and tegulae blackish. 



e. Prothorax black, only the posterior border ferruginous. 



/'. Angles of post-scutel, post-tegulae, and border of petiole 

 yellow. 



%. Smaller. Clypeus grayish-silky. Antennae with a little 

 ferruginous hook. The frontal spot, scape beneath, margin of 

 petiole yellow. 



I'm-. Prothorax black ; its hinder margin yellow ; post-scutel 

 ■x ; margin of the abdominal segments yellowish. 



Common variety. — Generally of small size. Body quite black; 

 scape and apex of the antennae beneath ferruginous. Posterior 

 border of prothorax, post-scutel, border of abdominal segment, 

 1-t, 2d, yellow; of the others dull-yellowish. Tegulae fuscous; 

 feel partly ferruginous. Petiole not so much dilated posteriorly, 

 more pyriforra than triangular. (5 9,2 %. Cordova.) 



Ress. a. diff.—A very distinct species by its largo convex 

 thorax and strongly 'punctured abdomen. The head and thorax 

 are much as in Thoracicus, but the dorsum of the thorax is regu- 

 larly convex, not deformed. In the little varieties, the thorax 

 gets smaller, and the petiole narrower than in Regulus, but the 

 puncl ured abdomen always enables one to distinguish the species. 



Bab. Mexico; the Oriental Cordillera; Orizaba, Cordoba, 

 Moyoapam. (12 9, 6 % ) 



1-1. E. thoracicus n. Bp.— Parvulus, niger fulvo-velutinus ; thorace 

 Bal ralido, globoso, superne deformi, mesonoti disco se.bbicaiinato, 

 utrinque foveolato et subgibberoso, sparse cribrato-punctato ; abdomine 

 impnnctato, petiolo postice piriformi ; corpore obscure rufo-variegato ; 

 Bcutellis rufis ; petiolo flavo-liinbato ; alia nebulosis. 



9- Total length, 10 mil'. ; wing, S ram. 

 o . Total length, 9 mill. ; wing, 7 mm. 



9. Bead and thorax as in 1'. aviculus. Clypeus punctured, 

 but not bicarinate, and parted by a groove at tip; having the tip 



