A REVISION OF THE BEETLES OF THE TENEBRIONID 

 TRIBE USECHINI, WITH DESCRIPTIONS OF A NEW 

 GENUS AND NEW SPECIES 



By Frank E. Blaisdell, Sr. 



Professor oj Surgery, Emeritus, Stanford Medical School, San Francisco, California 



The following revision is the direct outcome of having received a 

 most remarkable addition to the tenebrionid tribe Usechini, which 

 was transmitted to me as a loan for study by the late Dr. E. A. 

 Schwarz and Mr. H. S. Barber of the United States National Museum. 

 A careful examination of the morphological characters of Usechus 

 lacerta Motschulsky, the only previously known member of the tribe, 

 revealed the need of a revision on account of a number of misstate- 

 ments in the literature regarding the generic and specific characters. 



It is, indeed, most surprising how errors regarding important 

 structural characters have been set forth and perpetuated in works 

 of a systematic nature intended for students' use. Such instances 

 of inaccuracy are coming to light quite frequently under modern 

 methods of study. 



In the Classification of the Coleoptera of North America (LeConte 

 and Horn), under the definition of the tribes of the Tentyriinae it is 

 said on page 360, that the eyes in the Usechini are round, and there 

 given in direct dichotomous comparison with the Zopherini, when as 

 a matter of fact the eyes are transverse in both of the tribes; and 

 again, in the descriptive citation of the characteristics of the Usechini 

 it is said (p. 365 of the classification) that the mentum conceals the 

 maxillae at base and the ligula in part, which likewise is not correct 

 for the cardo and stipes visibly fill the buccal fissures in the species 

 described below. Another misleading statement (p. 365) is that 

 regarding the antennae which are described as " ten-jointed, as the 

 eleventh is closely united with the tenth, and is represented only by 

 a pubescent space at the tip of the latter." Such is not the case, 

 however, for the eleventh joint is oval, and more or less feebly trans- 

 verse and not so closely united to the tenth as to be difficult of 

 observation. In the Revision of the Tenebrionidae of America, Horn 

 repeats the error regarding the eyes (p. 257) but corrects that con- 

 cerning the eleventh antennal joint (p. 273). 



No. 2790.— Proceedings U. S. National Museum. Vol. 75, Art. 19 



40747—29 1 



