CROCODILIANS, LIZARDS, AND SNAKES. 

 Natrix fascia ta transversa Jlallotrcll. 



975 



Locality. 



New '.raiiiilels, Texas. 



Indifiuola, Texas 



Rio Pecoa, Texas , 



Antelope Creek 



Fort Smith, Arkansas 



Creek boundary , 



Hot Si)rings, Arkansas ... 

 Guadalupe River, Kerr- 



ville, Texas. 

 Quinlan Creek, Kerrville, 



Texas. 



When 

 collected. 



-, 1858 



■ From whom received. 



r. Lindheimer. 



Nature of 

 specimens. 



Alcoholic. 



do. 



do. 



Col. J. D. Graham, V. 



S. A. 



Capt. JohnPope, r. S. A. do. 



H. B. Mollhausf'ii ] do. 



Lieut. A. W. Whipple, do. 



U. S. A. 



"Wurdeiuau Alcoholic 



i type. 



H. H. and C. S. Briniley..! do. 



Ily. Caudlin j do. 



-do. 



do. 



This form is restricted to Texas and adjacent regions, where it is 

 abundant. 



NATRIX FASCIATA ERYTHROGASTER Shaw. 



Natrix fasciata erythrogaster Cope, Proc. U. S. Nat. Mus., XI, 1888, p. 392. 

 Coluber erytln'of/asier Shaw, Gen. Zoology, III, 1802, p. 458. — IIolbrook, N. 



Amer. Herpt., II, 1838, p. 91, pi. xix. 

 Tropidonotus erythrogaster Holbrook, N. Amer. Herpt., 2d ed.. Ill, 1842, p. 33, 



pi. viii. — DuMERiL and Bibron, Erp. Gen., VII, 1854, p. 570. 

 Xerodia erythrogaster B.\ird and Girard, Cat. N. Amer. Eept., Pt. 1, Serp., 1853, 



p. 40. 

 Tropidonotus sipedon erythrogaster Cope, Check-list N. Amer. Batr. Rept., 1875, 



p. 43. 

 Tropidonotus fasciattis var. erythrogaster Boulenger, Cat. Snakes Brit. Mus., 



I, 1893, p.* 244. 



Head elongated, narrowing forward. Gastrosteges most numerous 

 of all the subspecies of the Natrix sipedon. Three i)Ostorbitals. An 

 elevjited loreal. Dorsal rows of scales, twenty-three, sometimes twenty- 

 five, in number, all very strongly carinated. Uniform dark bluish 

 black above, lighter on the sides; a lateral or external band of dull 

 blue extending on the abdominal scutelke. Body beneath (in alcohol) 

 uniform dull yellow, tail bluish. 



The head is proportionally narrow and elongated, flattened above 

 and convex on the snout. The frontal plate is elongated and sub- 

 pentagonal, broader anteriorly than posteriorly, with tlie sides slightly 

 concave. The jjostorbital plates, proportionally small, are three in 

 number. Loreal large and polygonal, higher than long. There are 

 three or four temporal shields very much developed, but one in contact 

 with postorbitals. Dorsal rows of scales twenty-three or twenty- four 

 in number, strongly carinated with the keels on the posterior third of 

 the body, constituting very conspicuous and continuous ridges, the 

 intermediate depressions or furrows giving to the body and tail a 

 canaliculated appearance. The lateral or outer row, however, is but 

 slightly carinated. The tail itself is subconical, very much tapering, 

 forming one-fourth of the entire length. 



