1899.] NATURAL SCIENCES OF PHILADELPHIA. 461 



15. Tlioi-ax short, almost square 16 



Thorax distinctly longer than broad 19 



IH. Thorax strongly punctured, the punctures neither very deep 



nor coarse; pronotum with scarcely any medial surface 17 



Thorax cribrose; pronotum with a distinct medial surface . 18 



17. Junctures of vertex irregular and somewhat confluent ; both 



scutel la yellow anteriorly conjiuenta ?. 



Punctures of vertex even, separated; scutella entirely black 



jjroxima ?. 



18. Petiole with basal stem tolerably stout . . . cribrosa ?. 

 Petiole with basal stem slender , . . cribrosa 9 Var. (?). 



19. Punctures of thorax very deep and widely separated; petiole 



unusually slender, longer than head and thorax, and with 



second dorsal, impunctate gracilis 9. 



Punctures of thorax closer and less deep; petiole and second 

 dorsal punctured 20 



20. Petiole less distinctly punctured than second dorsal, the en- 



larged portion, seen from the side, evenly and not very 



highly, convex invemista ? . 



Petiole more strongly punctured than second dorsal, the en- 

 larged portion, seen from the side, highly convex or arched 



fornicata cT. 



21. Second dorsal segment, viewed laterally, subangulate toward 



base, its upper surface appearing flat, having a straight con- 

 tour (insect marked wath rufous) .... deforma ?. 

 Second dorsal segment convex 22 



22. Thorax or abdomen not marked with rufous; abdomen with 



short, thin, brownish hairs, especially on second dorsal 



])ilosa 9 . 

 Thorax or thorax and abdomen more or less reddish . . 23 



23. Clypeus broader than long; petiole rather stout; dorsuluni 



entirely black; tegulse punctate tegularis ?. 



Clypeus about as long as broad; petiole more slender; dorsu- 

 luni with two red strijoes; tegulte impunctate 



tuberculata $cf- 



24. Thorax maculated with rufous .... rufomaculata 9. 

 Thorax maculated with yellow .... fulvomaculata 9 . 



Montezumia chalybaea Sauss. 

 One specimen. Santarem, 



