VARIATIONS OF GARTER-SNAKES. 85 



scales are a dull brick red, giving rise to a pattern that resembles very- 

 much some specimens of parietalis from the same region. This speci- 

 men is, however, the only one which we have observed with this 

 development of red pigment, and the trait must be considered as of 

 rather uncommon occurrence and not as typical of specimens from 

 this region. 



The "haydeni" type of color, as above described, may be considered 

 in general as typical of specimens from South Dakota, Wyoming, 

 Nebraska, Colorado, and Kansas, but to the east and north of these 

 points the ground color becomes darker brown, and even black, some- 

 what or entirely obscuring the spots. The stripes in prairie specimens 

 remain much the same as in western ones, but the dorsal tends to lose 

 its golden tinge. Doctor Coues (1878, 277-278) states that Pembina 

 specimens are "olivaceous-blackish or obscure brownish black," and 

 that this color occurs as far westward as the Coteau de Missouri on 

 the northern boundary^, but that in the arid region of the upper Mis- 

 souri and Milk rivers it is replaced by a form w^hose principal char- 

 acter is seen in the increased breadth and intensity of coloration of 

 the dorsal band, especially on the anterior portion. To this western 

 form Coues and Yarrow (1878, 279-280) gave the name of radix 

 twiningii. Western Iowa specimens are as a rule darker than those 

 from Kansas and Nebraska, and show their close color affinity mostly 

 in the golden yellow dorsal stripe, and it is evident that these speci- 

 mens are to be considered as intermediate between the more pallid 

 western pattern and its darker eastern representative. That the color 

 tends to become darker to the northward as w^ell as to the eastward is 

 shown by the fusing of the spots on the skin in specimens from Turtle 

 Mountain and Regina. 



The third color variety has been described by Cope (1888, 400-401) 

 on the basis of two specimens reported to have been taken at Brook- 

 ville, Indiana (see p. 80). The principal characteristic of these speci- 

 mens was the elongation and fusion of the gastrostegeal spots to form 

 a broken band along each side of the abdomen; not an uncommon 

 occurrence in the darker eastern representatives of this form. 



None of these phases differ sufficiently to indicate w^ell-marked 

 forms or to be given subspecific rank, and they have been dropped by 

 later writers. 



In the above discussion of the variations of radix I have purposely 

 excluded from consideration three specimens (Nos. 30872, 30873, 

 30874) in the U. S. National Museum from Milwaukee County, Wis- 

 consin. These specimens are typical hutleri in coloration, and the lat- 

 eral stripe is up^n the third and adjacent halves of the second and 

 fourth rows. In scutellation they agree both with hutleri and with 

 reduced specimens of radix. The scutellation is as follows: 

 33553— Bull. 61—08 7 



