Reptiles 109 



genera have the anal plate undivided; Lampropeltis, with 19 to 25 

 rows of smooth scales, and Pituophis, with 29 to 35 rows of scales. 

 They are not at all alike; the King Snake {Lampropeltis triangulum 

 gentilis of Baird and Girard) is rather small and beautifully 

 banded with red, black and light yellow. It is not uncommon 

 east of the mountains. The Bull Snake (Pituophis sayi of Schlegel) 

 is very large (up to eight feet), and part of the dorsal scales are 

 keeled. The back is spotted. It is common about Boulder and 

 Denver. A western form (P. bellona of Baird and Girard) was 

 obtained by Beardsley at Fruita. The name bellona seems to be 

 of uncertain application, as Van Denburgh indicates that it has 

 been applied by various authors to at least six different kinds of 

 Pituophis. In the remaining seven genera the anal plate is divided. 

 The scales are distinctly keeled in Heterodon, Natix and Storeria; 

 smooth or very faintly keeled in the others. The Hog-Nosed 

 Snake (Heterodon nasicus of Baird and Girard) is very easily 

 known by the upturned snout. It is common on the plains. 



The Water Snake (Natrix sipedon of Linnaeus) is semi- 

 aquatic, with dull scales in 23 or 25 rows. The body is crossed by 

 numerous dark bands, more or less broken into spots on the back. 

 Specimens have been taken at Boulder, Denver, Wray, and other 

 places. De Kay's Snake (Storeria dehjayi of Holbrook) has strong- 

 ly keeled scales in 1 7 rows. There is a pale stripe down the back, 

 and on each side of this a row of dark spots. A specimen was 

 obtained by Beardsley in Las Animas County. 



The Green Snake (Liopeltis vernalis of Harlan), green above 

 and pale below, with 15 rows of smooth scales, has been taken 

 at Boulder and Palmer Lake. The Ground Snake (Sonora semian- 

 nulata of Baird and Girard), which is identical with the Contia 

 isozona of Cope, was secured by Beardsley in Las Animas County. 

 It has 15 rows of smooth dorsal scales, and is very conspicuously 

 transversely banded, the pale ground color often reddish. The 

 two last genera, peculiar for the two nasal plates on each side, are 

 Diadophis and Coluber. In the Sonoran Ring-Necked Snake 

 (Diadophis regalis of Baird and Girard) there may be a yellow 

 collar, or it may be absent. The general color above is dark 

 brown to bluish-black, and the under surface is yellow, turning 

 to bright red posteriorly. It is known from Trinidad. The 

 species of Coluber are marked with cross-bands or spots when 



