Vol. VIII] VAN DENBURGH AMD SLEVIN— GARTER-SNAKES 235 



S1202, S1203, S1204, S5183, SR.7, S4157, S6378, S6380, 

 SR.69. SR.64. SR.65, SR.67, S6520, S5852, S4151, 

 S4152, S4153, and S4307, or in twenty-nine of three hundred 

 and sixty-three specimens, or 8%. All of these specimens are 

 from the San Francisco peninsula, that is to say, from San 

 Mateo, Santa Clara, Santa Cruz, and Monterey counties. They, 

 however, share this area with snakes of various other styles of 

 coloration, and all sorts of intermediate specimens are to be 

 found, so that this seems to be merely a peculiar color phase, 

 although restricted geographically to a small portion of the 

 range of the subspecies. 



In certain specimens the dorsal line is lacking, or very faint 

 or short. This is found most frequently in specimens from 

 Humboldt and Mendocino counties. 



Specimens from San Francisco and Marin counties usually 

 may be recognized as such by their coloration, which is of a 

 style not peculiar to these areas, but certainly most frequent 

 there. There are three lines, the dorso-lateral region is largely 

 red with dark spots, and the belly often is more or less suffused 

 with bright brick red. 



Perhaps the most frequent style of coloration is that which 

 shows three light lines on a brown or olive ground, with the 

 belly yellow or olive. But, as we have said, individual varia- 

 tion in color is enormous. 



One specimen (No. C2452) contained a Bascanion vetustum. 

 This is the only instance we recall of a snake having been eaten 

 by Thamnophis. 



Thamnophis ordinoides elegans (Baird & Girard) 

 Mountain Garter-Snake. 



Diagnosis. — Normally with eight supralabials ; twenty-one, 

 or sometimes nineteen, rows of scales ; dorsal line very distinct, 

 narrow; dorsal spots lacking or not evident, being hidden by 

 the dark ground color, not invading the edges of the dorsal 

 line ; gastrosteges rarely marked with black or slate ; preocular 

 almost always single ; infralabials very rarely more than ten. 



Type Locality. — El Dorado County, California. 



