- 



BYMENOPTERA OF AMERICA. [ PART I. 



puuctured, but ool more on \U margin than elsewhere; the third 

 sely punctate; the following impunctured ; the first 

 margin of the 2d a little arcuate and depressed in the middle; 

 the si cond lamellar margin of 2d and 3d segment growing a little 

 wider on the sides; thai of the 3d rather transversely cut out in 

 iddle third. Posterior tibiae arcuated, a little deformed. 



Black, with a very dull silky reflection, rather fulvous. .Mouth, 

 3, and clypeus, yellow, a little orange, or reddish at top 

 of clypeus. Scape and the end of flagellum beneath, yellowish 

 or tawny. Two spots over the antennas, two lines on the vertex 

 starting from the eyes, and two lines behind the eyes, not marginal, 

 tawny. Both margins ofprothorax and two spots on the lateral 

 margins of scutellum, yellowish-tawny ; two spots on the edges 

 of post-scutel, the margin of petiole and a narrow yellow sub- 

 inal line on the second segment, yellow; anterior feet more 

 or less ferruginous or yellow-tawny beneath. Wings subhyaline; 

 veins In-own; 2d cubital cell lengthened at base (on the side 

 looking to the b'ase of the wing). 



9. Clypeus rounded, densely and strongly punctured; a little 

 velutinous ; its inferior margin arcuate, not truncate nor emargi- 

 nate; its summit a little carinate. The head beneath and around 

 the mouth, post-sternum and anterior coxae, sulphur-yellow. 



%. Clypeus a little wider, having the same shape and color as 

 in the ?. The oblique cutting border of mandibles with but 2 

 little notches. Antenna' tawny beneath; the last two joints obtuse, 

 forming nearly a hook. Anterior til>ia>, tarsi, and thighs beneath 

 ferruginous; intermediate tibiae beneath and 1st, 2d, and 3d joints 

 of the tarsi beneath yellow ; the 3d segment slightly margined 

 with yellow. 



Var, Prothorax black, with its angles and two marks, tawny. 



Hab. .Mexico. The Oriental Cordillera. Orizaba (Mr. Sumi- 

 chra 



Rests, a. diff. — This is a very distinct species in the remarka- 

 ble form of its metathorax and the rugosities of its petiole; quite 

 different from all other Mexican Zethus, except from clypeatus. 

 It differs by its more excavated metathorax. the excavation being 

 polished and more carinated, anil by its prothorax, more rounded 

 anteriorly, not square shaped nor crested on the sides; by its 

 rougher petiole, carinated in the middle, etc. It has such 

 an extraordinary resemblance to Z. miniatus that it might be 



