114 HYMENOPTERA. 



"A. Tubercles wholly black. 



1. Wings tinged grayish, mesothorax pubescent... Siibdigitata. 



2. Wings tinged brownish, mesothorax bare digitata. 



B. Tubercles partly yellow. 



^. Comparatively large, face white, scape wholly white in front. 



bakeri. 

 2. Face pale yellow, scape with at most a yellow mark. 



a. Larger, wings tinged brownish ruidoseiisis. 



b. Smaller, wings tinged grayish riidbeckife.'* 



Such distinctions, altho perhaps appearing quite final in a 

 small series, are of no value whatever as specific characters, 

 in the light of the preceding facts. I have the Baker collec- 

 tion containing the lots from which most of these were de- 

 scribed, and have examined types or authentic specimens of 

 all but digitata, and they cannot be separated except as forms 

 or varieties as given above. 



In addition to the preceding variations there is one in 

 which the modification is in the genital characters instead of 

 face marks. This I have called P. rjidbeckics var. gj^annlatus 

 from the granulated appearance of the eighth ventral plate 

 which resembles in this respect that of P. cressoni, (fig. 54). 

 This plate is intermediate between that of cressoni and rtid- 

 beckice, having the granulated appearance of the former, but 

 with dark chitinized portions suggesting the horn-like pro- 

 jection of the latter. In face markings this resembles var. 

 bakeri, but lacks the yellow on the scape, (fig. 88). I have 

 three male specimens of this variety, all agreeing with this 

 description. 



PROSOPIS CONSPICUA n. sp. 



Male. — Distinguished by its large size, greatly swollen scape, greatly 

 dilated upper extension of lateral face marks, fine dense puncturation 

 of thorax, yellow on collar, tubercles, and tegulaj ; and by the long 

 narrow wings of the seventh ventral plate. 



Large, about 6-7 mm. in length; scape stout, greatly dilated and 

 flattened ; face rather narrow ; antennal sockets close together, (fig. 

 91); clypeus less than one-half as wide at base as at apex, somewhat 

 narrower at base than lateral face marks at same level. Thorax and 

 abdomen stout ; propodeum rather short, without any conspicuous 

 superior face. 



Sculpture. — Front and vertex conspicuously punctured with moderate 

 sized, round punctures, becoming confluent near antennal sockets ; 



