46 REGINA. 



Ground-color dark chestnut or chocolate-brown above, marked with 

 three narrow black vittse or bands, one covering the medial row of 

 dorsal scales, and two (one on each side) following the fifth row. A 

 lateral yellow band occupies the upper half of the outer row and the 

 whole of the second row, thus broader than the black bands above. 

 Immediately below, and contiguous to it, a somewhat larger brown 

 band covers the lower half of the outer row of scales and the ex- 

 tremity of the abdominal scutellge. The abdomen is yellowish, pro- 

 vided along its middle region with two approximate brown bands, 

 similar though a little narrower, and interrupted by the yellowish 

 edge of the scutellas. The tail beneath is almost rendered uniformly 

 brown by the confluence of the bands. 



2. H-CglBia. rigida, B. & G. — Greenish brown above ; two deep brown 

 vittae along the dorsal region. Contiguous edges of the outer row of scales 

 and abdominal scutellse finely margined with brown. The middle region of 

 the outer row like the abdomen, as is that of the second row, but less dis- 

 tinctly. Abdomen reddish yellow, with two series of black spots on the 

 middle region, approaching each other towards the anterior region of the 

 body. Dorsal rows of scales 19, carinated except the outer row, which ia 

 smooth. 



Syn. Coluber riffidus, Say, Journ. Acad. Nat. Sc. Philad. IV, 1825, 39.— 

 Harl. Journ. Acad. Nat. Sc. Philad. V, 1827, 355 ; and Med. & Phys. Res, 

 18.35, 118. 



Tropidonotus rigidus, Holbr. N. Amer. Herp. Ill, 1842, 39. PI. x. 



Head proportionally larger than in R. leberis, much less depressed 

 and shorter on the snout. Its upper surface is flat, the snout convex, 

 the high and large rostral making it less sloping. Vertical plate 

 .^ubhexagonal and elongated. Occipitals truncated posteriorly. Su- 

 perciliaries narrow and tapering forwards. Anterior pair of frontals 

 very small. Two postorbitals of nearly equal size, and two ante- 



