116 HERPETOLOGY OF MICHIGAN. 



THAMNOPHIS BUTLERII (Cope). 



BUTLER GARTER SNAKE. 



Eutainia 'bracluj stoma, Clark, 1903a, 1904, 194. 

 Eutaenia 'butler i, Notestein, 114. 



Thamnopliis lutleru Clark, 1905, 109. Rntliven, 1904, 289-299; 

 1909a, 116; 1908, 87-9G; 1911a, 2G8-2G9. Wliittaker, 1905. 



Description: A small rather thick-bodied snake attaining a 

 length of about twelve inches. Head small and usnally not very 

 distinct from neck, somewhat elevated behind, and sloping qnickly 

 down to the point of the snont. Muzzle short. Sides of head 

 moderately high, concave in preocular region. Eye small. Cephalic 

 plates normal; two nasals and one loreal. Nostril lateral, between 

 the nasals. 



Dorsal scales usuallv 19-17, occasionally 17-19-17 or 17-19-17-15. 

 Supralabials 6 or 7, rarely 8, average between 6 and 7 ; infralabials 

 G, 1, 8, 9, or 10, average between 8 and 9. Temporals 1 in first 

 row and 1 large or 1 large and 1 small in second row. Ventrals 

 134-14G (males), 132-140 (females), subcaudals Gl-GG (males), 49-58 

 (females). Anal plate single. 



Ground color above some shade of dark olive brown, with three 

 (a dorsal and two lateral) bright yellow or greenish yellow stripes. 

 The dorsal stripe is usually on the median and halves of the ad- 

 jacent rows, and .the laterals upon the third and more or less of the 

 second and fourth rows. The color of the first and adjacent half of 

 the second rows of scales is generally not lighter than the ground 

 color above. There are two rows of black spots on the skin — en- 

 croaching on the scales along the stripes in specimens light enough 

 to show them — but these often lose their identity' by fusing irregu- 

 larly. Belly pale greenish, the only markings being a small black 

 spot at either end of each ventral scute. 



Habits and Habitat: The following account of the habits of this 

 snake is taken from the monograph of the genus by the 

 writer (Ruthven. 1908, 89-91) ; ''In southern Michigan I have only 

 taken it in the immediate vicinity of water, either about the margin 

 of swampy places or on the banks of streams. This may be a coin- 

 cidence, but it is in accord Avith all of the specimens collected 

 throughout the range which have habitat data. I have found them 

 most frequently by overturning boards, etc., in such places, al- 

 though they are also found crawling about in the long grass and 

 herbage. 



'"It is in disposition a rather sluggish snake, seldom attempts to 



