1901.] NATURAL SCIENCES OF rillLADELPIIIA, 39 



infold examples is not easy to make out. Length 1,200 mm. (tail 

 260). 



Hab. — Florida to New Orleans, and sparingly up the Missis- 

 sippi to southern Illinois. 

 Tropidonotus taxispilotus Ilolbrook. , 



No. Am. Herp., IV, 35, PI. 8 (1813); NerocUa tnxispilotua B. and G., 

 I. c, 43 ; Natrix taxispilota Cope, I. c, 674, anti Kep. Nat. Mus., 959; 

 T. taxispilotus Bonl., I. c, I, 215. 



Largest of the American water snakes ; body very stout ; scales 

 in 29-33 rows, strongly keeled ; oculars 1-2 (3); temporals 2-4 

 (5); the parietal shields are small, their hinder portion being 

 usually broken up into small plates ; upper labials 8, usually only 

 the fourth entering the eye: ventrals 130-148; subcaudals 70-90. 



Reddish brown, with a dorsal and lateral series of rectangular 

 blackish brown blotches, which alternate but do not touch; belly 

 yellowish white with irregular blotches of dark brown. This 

 species resembles both T. s. transversus and T. rhombifer, but may 

 always be known from the former b}'' the increased number of scale 

 rows, and from the latter by the absence of the oblique bars con- 

 necting the dorsal and lateral spots. An occasional specimen 

 shows the orbital ring of scales fouud in T. cyclopiani. Length 

 1,300 mm. (tail 290). 



Hab. — From the Potomac river to Florida and New Orleans. 



SEMINATRIX Cope. 



Am. Nat., 1895, 678, and Rep. Nat. ]\Ias., 993; Contia (part) Cope, 

 I. c, 599; Tropidonotus (part) Boul., I. c, I, 192. 



jNIaxillary teeth smooth, slightly increasing posteriorly, tin last 

 two abruptly enlarged ; body rather stout ; head small and slightly 

 distinct; head scales normal; one loreal; nasal half divided; no 

 scale pits; scales smooth on body, sometimes faintly keeled on the 

 tail. 



Hab. —Florida. 



Seminatrix pygsea Cope. 



Contia pygcea Cope, Proc. Acad. Pbila., 1871, 222, and I. c, 600; S. 

 pygcE'/s Cope, Am. Nat., 1895, 678, and Rep. Nat. Mas., 993 ; Tropi- 

 donotus pygceus Boul., I. c, I, 228. 



Size small, tail short; 20-24 maxillary ]teeth, smooth and slightly 

 increasing posteriorly, the last two abruptly enlarged; mandibular 

 teeth about 20, subequal; head scales normal; internasals small; 



