IOWA ACADEMY OF SCIENCES. 197 



The examination of several hundred examples embracing 

 some twenty sp3cies at present referred to five different genera 

 and incluiing all of the above mentioned variations compel the 

 rejection of the cross nervure as an absolute character, or one 

 capable of even specific recognition, except as correlated with 

 other characters, and the re- establishment of the Burmeisteran 

 genus based on head characters. It may be noted, however, 

 that when thus restricted, it contains no species lacking the 

 cross nervure nor any in which it is found to be variable. 



The material upon which the revision has been based, and 

 which has been accumulating during a numbar of years past, 

 consists mainly of the following: Types of the ten VanDazee 

 species; types or typicil specimens of all but two of the Gillette 

 and Baker species, together with a series of several hundred 

 Colorado specimens, received through the kindness of Professor 

 Gillette. Twenty European species of the genus as defined by 

 Melichar, more than half of them direct from him, which, in 

 connection with his recent synopsis, f arnish a good basis for 

 comparison of the American and European faunae. The Van 

 Duzee material in the genus outside of the types, which, 

 together with them, includes all but one of the eighteen 

 described species which he listed in his catalogue. And, lastly, 

 the college collections of thousands of specimens of adults and 

 larvse, together with a large series of balsam mounts of larvae, 

 elytra and wings, structural details and dissected genitalia for 

 microscopic examination. These, embracing twenty- five spe- 

 cies, among them the one lacking from the VanDuzee material, 

 and thus complete the series of described American species. 



After restricting the genus it was found that it could be sep- 

 arated into three well defined groups, each of which has its 

 parallel in the European fauna. In fact, two out of the three 

 groups possess species common to both continents. The first, 

 or reflexed veined group includes species with short pronotum 

 and sharp margined head; the elytra have little or no appendix 

 and the costal veinlets are white-mirked, strongly reflexed in 

 one series and nearly right-angled in another. Of this group 

 biUneatus represents one extreme and is closely related to the 

 European formosus, while ocellaris common to both continents, 

 and sayi closely related to the European ^ori and socialis, repre- 

 sents the other. They agree in being of a general light brown 

 color with definite markings, and are two-brooded as far as 

 known. The larvae are light, with four brown stripes. The 



