13. COLUBRID.r. 



Remarks. — This is the common garter-snake of the 

 northwest coast. It is of small size. The largest specimen 

 examined measures 590 mm. to base of tail. The head is 

 small, not so distinct from the neck as in other races, and 

 the labials are reduced in number. 



The coloration is very variable. The dorsal line fre- 

 quently is absent or developed only on the neck. The 

 lateral lines also may be absent. Specimens may be heavily 

 spotted or without any marking, either lines or spots. The 

 dorsal line usually is yellow, but may be red, and there 

 often is red elsewhere in the coloration, as on the gastro- 

 steges. The lower surfaces often are dark, and the colora- 

 tion everywhere may be very dusky. 



Specimens with heavy spotting and dark pigmentation 

 of the gastrosteges resemble T. o. vagrans, but usually may 

 be easily distinguished by their scale characters. 



Specimens showing no dorsal line resemble T. o. couchii, 

 but here again the scale characters are quite different. 



The closest relationship of this sub-species undoubtedly 

 is with T. o. atratus, yet there can be no doubt as to the 

 subspecific distinctness of the two forms. The differences 

 in the number of superior and inferior labials, scale-rows 

 and gastrosteges should be sufficient aid toward their cor- 

 rect determination, and the general appearance usually is 

 quite different. Certain specimens, however, are so nearly 

 intermediate in one or more of their characters that students 

 might differ in opinion as to their identity. Such specimens, 

 as set forth under head of T. o. atratusy show real geo- 

 graphic intergradation. So far as specimens examined by 

 us show, this intergradation occurs only in Del Norte 

 County, California, where the ranges of the two forms meet 

 and perhaps overlap slightly. Many of the specimens from 

 this county are typical of either one or the other subspecies, 

 — ordinoides or atratus, — and most of the intergrades seem 



