Dec, I9I2.] Fall: North American Collops. 249 



A REVIEW OF THE NORTH AMERICAN SPECIES 

 OF COLLOPS (COL.). 



By H. C. Fall, 

 Pasadena, Cal. 



For upward of forty years the table of species of Collops and 

 brief accompanying notes, published by Dr, Horn in 1870, has been 

 the sole means by which American students and collectors have iden- 

 tified their material, and as such has done good service. There are 

 however one or two positive errors in the table, and this fact together 

 with the desirability of incorporating the considerable number of new 

 species herein or recently described has led to the preparation of 

 a new table. While the material upon which the present paper is 

 based has not been sufficient for an exhaustive review, it is believed 

 that the table together with the following descriptive and compara- 

 tive notes — brief or detailed as seems necessary in each case — will 

 enable the student to identify nearly everything now in collections 

 with tolerable accuracy. Positive identification with females alone 

 is often impossible, and in the material examined I have left a num- 

 ber of such unplaced, one or more of which may prove to be new 

 when males are found. 



Notwithstanding its instability there can be no doubt that color 

 offers the simplest and most useful means of dividing the genus into 

 primary groups. The tendency to variation in color appears to be 

 very slight in some species while in others of quite similar type it is 

 strongly in evidence; in all cases however it manifests itself in certain 

 definite directions. In species with elytra normally maculate the 

 spots may vary in size and often have a tendency to coalesce and 

 form vittse. In the normally vittate species the variation is in the 

 reverse direction, the vittse becoming more or less narrowed at the 

 anterior third or even entirely divided. The thoracic spot is prone to 

 vary much in size and may be present or entirely absent in the same 

 species. The extreme of variation in this respect is shown in versa- 

 tilis, in which the thorax may be entirely red, entirely black or with 

 intermediate forms. The color of the legs is fairly constant in a few 

 species but is subject to more or less variation in the greater number, 



