376 PROCEEDINGS OF THE NATIONAL MUSEUM vul. lis 



material studied, each is somewhat (or sometimes highly) variable, 

 and intergrades may be found in the future. 



Dicosmoecus atripes (Hagen) 



Figures 2a-/ 

 Platyphylax atripes Hagen, 1875, p. 600. 



Dicosmoecus jucundus Banks, 1943, p. 358, figs. 102, 108, 118. [New synonymy.] 

 Dicosmoecus nigrescens Banks, 1943, p. 359, figs. 88, 90, 93, 96. [New synonymy.] 



This species appears to be the most variable in the genus, especially 

 in the armature of the lateral sheaths of the aedeagus. There is a 

 great variation in the number of spines present and in their arrange- 

 ment. In general the species may be said to possess sheaths that 

 are round or slightly depressed, generally bearing on the outer side 

 (but sometimes on the inner also) a variable number of rather long, 

 slender spines. The upper end of the basal ridge of the clasper is 

 barely separated from the ridge and not developed into a sharp 

 spine. Figures are given of the lateral penis sheaths of the holotypes 

 of atripes, jucundus, and nigrescens, as well as 3 other specimens, 

 to show the degree of variability encountered in this species. 



The types of all three species as well as other males from Colorado, 

 Utah, New Mexico, California, Montana, Wyoming, and Idaho 

 were studied. 



Dicosmoecus gilvipes (Hagen) 



Figures 2g,h 

 Platyphylax gilvipes Ilagen, 1875, p. 601. 



This is a large species often with the veins strongly marked with 

 fuscous. The lateral sheaths of the aedeagus are quite constant and 

 distinctive in structure. The sheaths are compressed and bear on 

 their upper and lower margins a row of rather short, broad spines 

 which vary greatly in number and exact placement. The basal ridge 

 of the clasper bears a distinct sharp tooth at its upper end. 



All the males Banks determined as D. grandis Ulmer are this species. 

 However, because the type of grandis is female and not in this country, 

 I am not synonymyzing grandis at this time. In addition to the type 

 of gilvipes, males from California, British Columbia, Nevada, Oregon, 

 and Idaho were seen. 



Dicosmoecus pallicornis Banks 



Figure 2i 

 Dicosmoecus pallicornis Banks, 1943, pp. 359-60, figs. 82, 83, 86, 87. 



In coloration this species is paler than the others, and the wings 

 are much more pilose. The lateral sheaths of the aedeagus are 

 distinctive, being short, blunt, and tipped by a cluster of short setae. 

 This species is known only from California. 



