H. C. FALL 455 



scarcely three-fourths the length of the boily, outer joints blackish, tenth not 

 quite three times as long as wide. 



Prothomx moderate, punctuation sparse except in the dark markings, smooth 

 along the side margins. Scutellum largely j^ellow. 



Elytra with a few irregularly placed punctures along the sutin-e at base, 

 otherwise completely striate, the striae feebly impressed, fifth and sixth often 

 a httle disturbed or irregular at middle; second interspace broad in the position 

 of the shield, gradually narrowing posteriorly and more rapidly so toward the 

 front; marginal interspace impunctate, eighth stria without post-humeral 

 interruption. The metiian vitta occupies imperfectly the third and fourth 

 interspaces; the external spot representing the end of an ex-terior vitta is on the 

 sixth interspace. 



Pygidium yellow with a broad basal margin and a fine apical margii^al line 

 terminating in a small dot each side, blackish. Legs yellow, hind thighs with a 

 fuscous median spot. 



Length 3.5 to 3.9 mm.; width 1.8 to 2 mm. 



Distribution. — New Mexico: Lone Mountain, Juty 7 (Cockerell); Albu- 

 querque, June 28 (Wickham). Arizona: (Soltau — Xat. Mus. Coll.), (Schaeflfcr 

 Coll.); Santa Rita Mountains, July (Snow); Prescott, July (Wsiw Dyke). 

 Texas: (Schaeffer Coll.); Chisos Mountains, July 10 to 26 (Wenzel). 



That this species is Suffrian's umbracidatus is probable but not 

 altogether certain. A specimen among some Mexican material 

 from the Nat. Mus. Coll. is so labeled by ]\Ir. Schwarz and seems 

 to fit the description sufficiently well. Others so named received 

 lately from the British Museum are less typical — judging from 

 the description — but apparently conspecific. Among this latter 

 material, howcn-er, are t\vo examples bearing name lahyrinthicus, 

 which are unquestiona1)ly identical with the Nat. Mus. umhrac- 

 idatus; evidently a mistake somewhere. And right here let me 

 say — as an example of the difficulty of obtaining reliably deter- 

 mined material, that I have received three examples from the 

 British Museum and two from the National jMuseum, purporting 

 to be lahyrinthicus. Of the former, two are apparently umhracu- 

 kitus as indicated above, the other is certainly different, while the 

 Nat. Mus. specimens (also from the Biologia Material) are quite 

 distinct from the other two. Some one of the three species may 

 be labyriuthicu.s l)ut only exj^ert comparison with the ty])e will 

 settle the c^uestion. 



L38. Pachybrachys pallidipennis Suffrian 



Robust, above yellow, head with standard black markings, 

 prothorax with heavy complete black M, elytra with the sutural 

 edge and tip of the shoulder knob black; elytra reguha-ly striate; 



TRANS. .\.M. EXT. SOC, XLI. 



