SCOTOPHIS. 73 



Genus SCOTOPHIS, Baird & Girard. 



Gen. Char. Foi-m colubrine. Body cylindrical, yery long — 

 many individuals attaining a very large size, perhaps the largest of 

 all North American serpents. Head elongated, rather narrow. 

 Vertical plate very broad, sometimes wider than long. Posterior 

 frontals very large. Postorbitals 2 ; anteorbitals one, generally very 

 large ; the longitudinal extension of this and of the postfrontals pro- 

 ducing a much elongated muzzle. Mouth deeply cleft, outline 

 nearly straight. Dorsal rows of scales 23-29 ; those along the back 

 slightly carinated (9-15 rows), on the sides smooth. Abdominal 

 scutellae from 200 to 235; posterior bifid. Subcaudals all bifid. 



Color brown or black, in quadrate blotches on the back and on the 

 sides, separated by lighter intervals. Abdomen usually coarsely 

 blotched with darker. In one species dark stripes on a light ground. 

 Although very large and powerful, many of the species of the genus 

 are characterized by their extreme gentleness, rarely becoming en- 

 raged, even when prJvoked. 



1. vScofopllis alleg'liailiesisis, B. & G. — Vertical plate longer 

 than broad. Posterior upper labial largest. Outer 7 rows of scales smooth. 

 Dorsal rows 27. Abdominal scutellse 235. Color black below, mottled 

 anteriorly with white. White edges to some scales, imparting an appear- 

 ance of dorsal and lateral blotches, especially in the young. 



Syn. Coluber alleghaniensis, Holbr. N. Amer. Herp. I, 1836, 111. PI. xx; 

 and 2d. ed. Ill, 1842, 85. PI. xix.— Dekat, New York Fauna. Kept. 1842, 36. 

 PL xii, fig. 26. 



Anterior frontals larger in proportion than in ^S'. Lindheimerii. 

 Superciliaries subtriangular. Upper labials 8, increasing behind ; 

 posterior the largest. Lower labials 11, 5th and 6th largest, de- 

 creasing posteriorly. Nostrils more in the anterior nasal. Outer 

 seven rows of dorsal scales smooth, then an obsolete carination, in- 

 creasing to the vertebral series. Each scale minutely bipunctate. 



General color lustrous pitch-black ; beneath, the color posteriorly 

 is uniform slate-black ; on the chin and throat dull yellowish : these 



