202 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.54 



ties. The former, Catostomus arenarius, is abundantly represented 

 in Owens River, while on the contrary it seems to be very rare in the 

 Lahontan system, where specimens are seldom caught. The cypri- 

 noids, Svphateles ohesus and Agosia rohusta, are common and widely 

 distributed Lahontan species. The poeciliid, Cyprinodon macula- 

 rius, is a form which has an irregular distribution in desert springs 

 and small streams of southern Nevada, California, and elsewhere. 

 Native trout have not been reported from the Owens River basin, 

 their absence calling to mind the similar case of Eagle Lake, which 

 has been reached by Lahontan catostomids and cyprinoids but not 

 by the trout. The trout of Eagle Lake is related to those of the 

 western slopes of the mountains. 



The fauna of Owens River has been largely derived from tiie 

 Lahontan system. Two of its species, C. arenarius and A. rohusta, 

 may have reached the river by stream capture, but the presence of 

 Siphateles offers some difficulty to the acceptance of a speculation 

 which would thus account for the invasion of the basin by Lahontan 

 species. The known species of Siphateles are lake and channel forms, 

 and none has yet been observed at a great distance up stream from 

 a lake, a deep spring pond, or a slough-like channel. 



CATOSTOMUS ARENARIUS Snyder. • 



SAND-BAR SUCKER. 



Representatives of but one species of Catostomus were secured, 

 and these belong to a form C. arenarius lately described from the 

 Lahontan system. \^1iere first discovered, the species appears to be 

 rare, for after considerable collectmg only nine specimens were obtained, 

 not enough to furnish very definite data regarding its characteristics 

 and distribution. Since, however, examples were taken in high 

 mountain streams, in the lower Truckee River, and in Pyramid and 

 Tahoe Lakes, one may be permitted to infer that its distribution is 

 rather general in the Lahontan system, and therefore equally so in 

 Owens River. Of its occurrence here Mr. Kennedy observes: 



Suckers are common everwhere in the main river, usually lying in schools on the 

 inflow side of the pools, with heads upstream. Some are very handsome fish, dark 

 olive brown, with the paler areas of the sides flecked with shining gold which fades 

 into yellowish white on the fins and ventral surface. Some are not so dark, gray and 

 white examples often being seen. 



Differences of a m^easurable character appear when examples from 

 Owens River and the Lahontan system are compared, the former 

 having somewhat smaller scales and longer fins. The differences are 

 slight, and they may perhaps disappear with the study of a larger 

 series of specimens. 



