48 REGINA. 



formly brown. Then again, a black vitta covering an entire row of 

 scales, and the edge of the row immediately under it, (the third.) 

 The first, second, and most of the third outer rows of scales are 

 straw-color. This yellowish band extends forwards, passing under 

 the head to the extremity of the snout. A black line is seen run- 

 ning from behind the neck to the anus, affecting the extremity of 

 the scutellse, and occasionally the lower edge of the outer row of 

 scales. The abdomen is uniform light straw-color ; a medial nebu- 

 lous blackish band under the tail is observable. 

 Rio Salado, Tex. 161+1. 57. 20. lOf. 2. Col. J. D. Graham. 



4. Regina Clarkil, B. & G. — Yellowisli brown, -with four longitu- 

 dinal bands of deeper brown. Abdomen dull yellow, with two clouded 

 brown bands dotted with black. One anteorbital. Dorsal rows of scales 

 19, all carinated. 



This is the largest species of the genus. Head elongated, conical 

 from occiput to the extremity of the snout, depressed above, subcon- 

 cave on the occipital region, slightly sloping on the snout. Cephalic 

 plates very much developed. Vertical subpentagonal, broader anteri- 

 orly, though slightly tapering. Anterior pair of frontals quite large. 

 Three and sometimes only two postorbitals, variable in comparative 

 size ; when there are three, the lowermost is suborbital. One ante- 

 orbital, large. Loral well developed, longer than high. Upper 

 labials 8, 5th and 6th largest, the latter very large. Scales of the 

 body elliptical, rounded posteriorly. Outer row somewhat larger 

 than the rest, and very slightly carinated. 



Color of head dirty brown, occipital and temporal region blackish. 

 Each of the four longitudinal bands of deep brown covers two rows 

 of scales. The intermediate yellowish brown spaces embrace each 

 two rows of scales also, except the dorsal one, which has three rows. 

 Each of the abdominal clouded bands embraces one-fourth of ab- 

 dominal space, inside of which is left a yellow space one-fourth of 

 the width, and exteriorly another yellow space one-eighth of the 

 width of abdominal space. The tail beneath is blackish, owing to the 

 confluence of the abdominal bands, interspersed with yellowish maculae. 

 Lidianola. 132+1.57.19. 31f. 6^. Col. J. D. Graham. 



