240 COLUBRID. 
41. Tropidonotus rigidus. 
Coluber rigidus, Say, Journ. Ac. Philad. iv. 1825, p. 239; Harl. 
Med. Phys. Res. p. 118 (1835). 
Tropidonotus rigidus, Holbr, N, Am. Herp. iv. p. 39, pl. x. (1842) ; 
Dum. § Bibr. vii. p. 577 (1854). 
Regina rigida, Baz rd j § Gans Cat, oy. Am, Rept. p. 46 (1853), 
Tropidonotus leberis, var. rigidus, Jan, Arch. Deol. Anat, Phys. iii. 
1865, p. 230; Garm. N. Am. Rept. p. 28 (1883). 
Natrix rigida, Cope, Proc, US. Nat. “Mus . Xlv. 1892, p. 668. 
Head small, scarcely distinct from neck ; snout very short. Eye 
moderate. Rostral broader than deep, visible from above; nasal 
semidivided ; internasals small, broader than long, shorter than the 
prefrontals ; frontal twice as long as broad, longer than its distance 
from the end of the snout, shorter than the parietals; loreal nearly 
as long as deep; two pre- and two postoculars; temporals 14+2; 
seven upper labials, third and fourth entering the eye; five lower 
labials in contact with the anterior chin-shields, which are nearly as 
long as the posterior. Scales in 19 rows, strongly keeled, outer row 
smooth, second feebly keeled. Ventrals 132-142; anal divided ; 
subcaudals 51-71. Olive-brown above, with or without a pair of 
blackish dorsal stripes; upper lip and lower parts yellow; two 
series of black spots along the belly, confluent into one anteriorly ; 
a black line along the middle of the tail. 
Total length 510 millim. ; tail 120. 
United States, east of the Mississippi. 
a. Yg.(V.141; C.61). Pensacola, Florida. C. Bollman, Esq. [C.]. 
uo ev. 142; 0. 62). N. America. Lord Ampthill P.). 
42. Tropidonotus grahami. 
Regina amii, Baird § Gir. Cat. N. Am. Rept. 47 1853) ; 
¥ Ace Bull. Iilin. Lab, iii. 1892, p. 273. me aie 
Tropidonotus grahamii, part., Giinth. ‘Cit p- 78 (1858). 
—— grahamii, Cope, Proc, Ae, Philad. 1861, p. 297. 
eberis, var. grahamii, Jan, Arch. Zool. Anat. Phys. iii. 1865, 
p- ~ p.229, and Icon, Gén. 27, pl. v. fig. 1 (1868) ; Garm. N. Am. Rept. 
p- 28 ( 1883). 
Netrix grahamii, Cope, Proc, U.S. Nat. Mus. xiv. 1892, p. 668. 
Head small, not distinct from neck. Eye rather small. Rostral 
broader than deep, visible from above; nasal semidivided ; inter- 
nasals narrow, longer than broad, as long as the prefrontals or a 
little shorter ; frontal once and two thirds to twice as long as broad, 
as long as its distance from the end of the snout, shorter than the 
parietals ; loreal as long as deep or deeper; two pre- and two or 
three postoculars ; temporals 14+2,; seven upper labials, third and 
fourth entering the eye; five lower labials in contact with the 
anterior chin-shields, which are much shorter than the posterior. 
Scales in 19 or 21 rows, very strongly keeled, outer row feebly or 
