794 13. COLUBRIDJE 



1 + 1 1+2 in one, or 8%. The supralabials are 7 7 

 in nine, or 75%} 7 8 in two, or 17%; and 8 8 in one, 

 or 8%. The infralabials are 10 10 in seven, or 58%; 

 9 9 in four, or 33%; and 9 10 in one, or 8%. The 

 scale-rows are 19 19 17 in all. The gastrosteges vary 

 in number from 157 to 168, males having from 164 to 

 168, females from 157 to 166; the average in five males 

 is 16 5. 4-, in seven females, 161.1. The urosteges vary 

 from 74 to 87, males having from 84 to 87, females from 

 74 to 79; the average in four males is 85.2, in four 

 females, 76. 



Distribution. This snake inhabits the great plains, 

 ranging west from Minnesota, Iowa and Missouri, to Utah 

 and perhaps eastern Nevada and southern Idaho. The 

 specimens at hand are insufficient to show the western 

 limits of the range of this subspecies and where and how it 

 meets, or merges with, or is replaced by, T. sirtalis concin- 

 nus and T. sirtalis infernalis. The last named form ranges 

 east at least to the western edge of Nevada, while T. sirtalis 

 concinnus seems to occur as far east as northern Idaho or, 

 possibly, Montana. Many more specimens are needed from 

 southern Idaho, eastern Oregon, and all parts of Nevada, 

 to throw light on these questions. 



I have examined Utah specimens from Cache (Bear 

 River at Logan), Davis (Woods Cross), Salt Lake (Fort 

 Douglas), and Utah (Spanish Fork), counties, and it prob- 

 ably is this snake which has been reported from Iron (Rush 

 Lake) and Utah (Provo), counties. 



I also have specimens from Bear Lake (Bear Lake) 

 County, Idaho. 



