190 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Se*. 



ber might not be largely increased if very much larger series 

 were at hand. We were able to distinguish easily, and with 

 but few errors, the snakes of Idaho from those of the Puget 

 region, and those of Palo Alto from those collected in the San 

 Joaquin Valley, as we picked them from a large pile of speci- 

 mens bearing numbers but no locality labels. The differences 

 are too intangible to describe, but they must exist, and may 

 become more evident when larger series can be studied. Some 

 of the color differences which we now regard as individual may 

 prove to be geographical, and the day may come when the 

 herpetologist, with enormous series, will emulate the orni- 

 thologist and mammalogist in the multiplication of subspecies. 



Thamnophis sirtalis parietalis (Say) 

 Prairie Garter-Snake. 



Diagnosis. — Squamation similar to that of T. s. concinnus 

 but coloration usually lighter and with more red, thus re- 

 sembling T. s. infernalis. 



Type Locality. — West side of the Missouri River, three miles 

 above the mouth of Boyer's River. 



Synonyms. — It seems that no other names have been based 

 upon individuals of this subspecies as here restricted. 



Range. — The great plains, west to Utah and perhaps eastern 

 Nevada and southern Idaho. 



We have examined specimens of Thamnophis sirtalis parie- 

 talis from the following localities : — 



1. Bear River, Logan, Cache Co., Utah. 



2. Fort Douglas, Salt Lake Co., Utah. 



3. Woods Cross, Morgan Co., Utah. 



Material. — Only 12 specimens have been studied by us. 



Variation. — The loreal is 1 — 1 in all. The preoculars are 

 1 — 1 in all. The postoculars are 3 — 3 in all. The temporals 



