Coleopterological Notices. 311 



hairs of the dorsal surface, and in its densel}^ pubescent legs. The 

 four specimens before me do not indicate any variation. 



COIVIOIVTIS Esch. 



A somewhat extensive genus, restricted in habitat to the true 

 Pacific coast fauna. In the latitude of Puget's Sound the species 

 extend into the mountains of western Montana, where specimens 

 of ovalis have been taken in the Bitter Root valley. Proceeding 

 southward, the eastern limit of range seems to approach the coast, 

 the area becoming gradually narrower, and finally vanishing with 

 a few peculiar species in the neighborhood of San Diego. It has 

 been stated that one species extends its range to the eastern slopes 

 of the Rocky mountains, but this is doubtful, there having been in 

 all probability some confusion of localities. Beyond the southern 

 limit, as here defined, the genus is replaced by the closely allied 

 Ccelotaxis, which is confined in habitat as far as known to the 

 single small island of Guadalupe. The geological conditions exist- 

 ing long ago in the Tertiary, which have given rise to this isolated 

 group of species, will be further discussed under the head of Coni- 

 ontis lata. 



There are several circumstances which render the identification of 

 the species a very difficult and uncertain task, even for the present 

 family, and among these should be mentioned the almost total 

 absence of any structural differences, also the marked persistence 

 and uniformity of type, and, at the same time, a considerable amount 

 of individual variation. It is almost absolutely essential therefore 

 to study large series of specimens, at least of several species, in 

 order that the peculiar laws of variation may be adequately appre- 

 ciated. The onl}^ noticeable structural variable, if such it can be 

 called, refers to the prosternal process, which is sometimes sur- 

 rounded by a fine convex bead and at other times simple, but I find 

 that this character is of but little value. 



Each puncture of the elytra bears a seta, sometimes erect, but 

 generally recumbent, occasionally extremely short, not projecting 

 notably beyond the puncture, but sometimes much longer ; after 

 careful study of extensive material, it seems probable to me that 

 this scanty vestiture may afford the best means of arbitrarily 

 grouping the species. It must be noted, however, that as these 

 setse are brittle and sometimes easily removable, care must be 

 AN.NAL3 N. Y. Acad. Sci., V, Nov. 1890.— 25 



