122 BULLETIN 31, UNITED STATES NATIONAL MUSEUM. 



Nevada, July 17; Fort Bridger, Wyo., August 4; Morino Valley, N. 

 Mex., July 1 ; W. L. Carpenter. One male and three females. — Osten 

 Saeken, 1. c. 



Description compared with the type specimen at Cambridge. 



Baccha costata. 



Baccha coataia S:iy, J. Acad. Phil., vi, 161 ; Compl, Wr., ii, 357. 



Habitat. — Indiana (Say). 



" Body black ; terguin with white bands ; head silvery ; a shining black 

 line from the vertex to the mouth, much contracted on the middle of the 

 front. Antennfe obsoletely honey-yellow at base. Occiput plumbeous 

 with a silvery reflection. Thorax black. Poisers white. Wings hya- 

 line with a somewhat narrow costal margin not reaching the tip. Scute 

 margined with yellow. Tergum black ; first, second, and third seg- 

 ments with an oblique white spot on each side at base, and remaining 

 segments tipped with yellow- white ; feet black ; anterior pairs, base of 

 the tibia, and tip of the thighs honey -yellow; posterior tibisB honey- 

 yellow at base. Length half an inch." — Say, 1. c. 



Baccha latiuscula. 



Ocjipfamus latiusculua Loew, Centur., vii, 68. 



Habitat. — San Domingo!, Cuba (Lw.). 



5,9. Length, 6™". Black, moderately shining. Front shining blue- 

 black ; in the male the frontal triangle large, shining black, narrowly 

 yellow on the sides. Face yellowish white, with a black stripe in the 

 middle, often obsolete. Antennaj black. Abdomen rather broad, de- 

 pressed, widest at tip of second segment, thence slightly narrowed ; in 

 color shining purplish black. Legs black. Wings black, towards the 

 posterior margin less so. 



Three male and one female specimens, San Domingo (G. F. Frazar.) 

 One male specimen, which is apparently the same, has the frontal tri- 

 angle nearly wholly yellow, the antennae in large part yellowish, a 

 small spot on the humeri and another on the post-alar callus, yellowish 

 red, the scutellum obscurely yellow, the abdomen chiefly opaque black, 

 with a large obscurely reddish -yellow spot on the angle in front 

 of the second and third segments, and the four front legs chiefly lute- 

 ous. It is apparently an immature specimen. Loe w's specimens showed 

 in a less degree similar differences. (" Scutellum aeneo-nigrum, vel 

 aiueo-piceum. Abdomen media segmentorum singulorum parte purius 

 nigra et magis opaca.") The species differs from B. dimidiata chiefly in 

 the wings not being hyaline on the outer part. 



Baccha cognata. 



Baccha cognata Loew, Centur., iii, 27. 



Habitat— ^ew York (O. S.) ! 



9 . Length, 7°"". Blackish bronze, head concolorous, the lower half 

 of the face and the antennae yellow. Humeri and pleurae yellowish. 



