40. THAMNOPHIS 837 



mens collected at Klamath Lake in southern Oregon. I 

 have examined specimens from Vancouver Island, from 

 Lillooet River Valley, British Columbia, the San Juan 

 Islands and King County, Washington, the South Fork of 

 the Coquille River, twenty miles above Myrtle Point, Coos 

 County, Oregon, the Rogue River near Grants Pass, 

 Josephine County, Oregon, Klamath Falls, Klamath Coun- 

 ty, and Lakeview, Lake County, Oregon, Gasquet, Del 

 Norte County, California, Lower Klamath Lake, Siskiyou 

 County, California, and Davis Creek and Goose Lake, 

 Modoc County, California. 



Specimens from northwestern Nevada, as those from 

 the Pine Forest Mountains, Virgin Valley, and Quinn 

 River Crossing, in Humboldt County, appear to be inter- 

 mediate between this form and true T. o. vagrant, the color- 

 ation being typical of the latter, while a tendency toward 

 an increase in the number of preoculars is still present. 

 These are listed with T. o. vagrans. 



Specimens from Grasshopper and Eagle lakes, Lassen 

 County, California, are intermediate between this subspecies 

 and T. o. elegans. 



Remarks. These snakes from the Klamath region are 

 very similar to T. o. vagrans, but the ground color of the 

 dorso-lateral regions usually is much darker. For this 

 reason the dark spots usually are inconspicuous. Occasional 

 specimens show the spots very distinctly, and in most speci- 

 mens they may be seen when looked for. These spots 

 invade the dorsal line just as they do in typical T. o. vag- 

 rans. The chief point of distinction between T. o. biscutatus 

 and T. o. vagrans is the increase in the number of preocu- 

 lars. Less than twenty-five per cent of the Klamath speci- 

 mens do not show this increase on at least one side of the 

 head, so that it must be regarded as a perfectly good sub- 



