Habitat: South-eastern United States, from North Carolina to Florida and the mouths of the Mississippi.
(5) C. horridus.—Supraoculars considerably narrower than the space between them, which is covered by 3-8 longitudinal series of small scales; 12-16 supralabials; body scales in 23-29 rows, dorsals very strongly keeled; 165-178 ventrals; 19-29 subcaudals.
Colour greyish-brown, usually with a rusty vertebral stripe, and V- or M-shaped blackish cross-bands; head uniform above, with a dark band from the eye to the angle of the mouth; usually a pair of roundish or triangular dark spots on the nape; belly yellowish, uniform or spotted with blackish; end of tail blackish.
Total length, 1,340 millimetres; tail 135.
Habitat: United States, from Massachusetts and Iowa to Northern Florida and Texas.
(6) C. tigris.—13-15 supralabials; scales in 23 or 25 rows, dorsals strongly keeled; 166-181 ventrals; 26-46 subcaudals.
Colour yellowish or pale brown, with a dorsal series of brown spots and cross-bands posteriorly; sides with smaller dark spots; belly yellowish, spotted with brown.
Total length, 380 millimetres; tail 50.
Habitat: Southern California, Lower California, Nevada, Colorado, Arizona, and Northern Mexico.
(7) C. mitchelli.—14-16 supralabials; scales in 25 rows, striated, dorsals strongly keeled; 178-198 ventrals; 24-26 subcaudals.