258 HYMENOPTEBA OF AMERICA. [PART I. 



chant ridges, but rounded and rugose, rarely elevated so as to be 

 separated from the post-scutel by a fissure, so that the post-scutel 

 appears very salient, The concavity striate, its borders rugose. 

 The superior crest salient or effaced. Abdomen wide, conical; 

 the first segment truncate, but rounded, without a ridge ; the 2d 

 segment finely punctured, offering along its posterior margin a 

 wide rugose band, a little depressed, garnished with coarse punc- 

 tures ; this band a little widened in the middle, but the little 

 border (the very edge) smooth; following segments strongly 

 punctured, with the extreme margin smooth. 



Blacl Variety. — Insect black; mouth, clypeus, a spot on the 

 front, inner border of the orbits, a great spot behind each eye, ai'ti- 

 cles 1-3 of the antennae, rufous; prothorax, tegulae, scutel, equally 

 rufous ; in the middle of the prothorax a double spot and on the 

 post-scutel a line or two dots, yellow; first abdominal segment 

 ornamented with a yellow border widened on the sides. Legs 

 black, knees, tibiae, and tarsi, yellow. Wings of a deep brown 

 violet. 



Var. a. Scutellurn black. 



b. Border of 2d and 3d abdominal segments brown. 



c. Border of 2d and 3d segments narrowly yellow. 



d. Clypeus black, spotted with ferruginous. Scutel black, with 

 two red spots. 



e. Disk of mcsothorax with two hooked rufous macula?. 



f. The ferruginous more extended ; two ferruginous spots on 

 the mcsothorax ; scutel and metathorax ferruginous ; abdomen 

 ferruginous with the first two segments notched with black at the 

 base nnd their border yellow (Louisiana) (Polistes dorsalis Fabr. 

 Rh. Louisianum Sauss.). 



g. Almost entirely ferruginous, with the border of the first 

 segment yellow. Legs, mandibles, orbits, varied with orange 

 (Illinois). 



//. The two metathoracic teeth blunted, not very distinct. 



Rufous Variety. — The whole insect rufo-ferruginous ; scape 

 beneath, hinder margin of prothorax, tegulse, a line on the post- 

 scutel, border of the 1st segment of the abdomen, yellow; feet 

 mostly yellow, and the flagellum only of the antennas black. — 

 Mexico. 



— a. A spot on the vertex, anterior part of mcsothorax, base 

 of the first two segments of the abdomen black (Tennessee). 



