w 



'V 



/p 



38 NERODIA. 



Genus l^Eff&ODIA, Baird & Girard. 



Gen. Char. Body generally stout, and almost all the species at- 

 taining a large size. Tail one-fourth or one-fifth of the total length. 

 Scales carinated. Cephalic plates normal. Anterior orbitals gene- 

 rally 1, occasionally 2 ; posterior 3, occasionally 2. Last and some- 

 times penultimate abdominal scutellas bifid; subcaudal, all bifid 

 or divided. Dorsal rows of scales 23-29. Abdominal scutellse 

 133-154. Subcaudal 66-80. General color, three series of dark 

 blotches on a lighter ground, sometimes almost uniform, brown or 

 blackish. Abdomen unicolor or maculated. Habits aquatic. 



I. IVerodia, Sipedon, B. & G. — Head rather narrow, elongated. 

 One anteorbital ; three postorbitals. Vertical plate smaller, and occipitals 

 larger than in JV. fasciata. Length of vertical equal to commissural line of 

 occipitals. Inframaxillary plates extending near to posterior extremity 

 of seventh lower labials. DwW brown, with narrow transverse light bands 

 margined with black. Dorsal rows 23. 



Syn. Coluber sipedon, Linn. Syst. Nat. I, 1766, 379. — Gm. Linn. Syst. Nat. 

 ed. xiii, I, iii, 1788, 1098.— Hakl. Journ. Acad. Nat. Sc. Philad. V, 1827, 

 351.— Thomps. Hist, of Verm. 1842, 118. 

 /- Coluber poecilogaster, Max. Wied. Eeise Inn. Nord. Amer. I, 1839, 106. 



Tropidonotus sipedon Holbr. N. Amer. Herp. fll, 1842, 29. PI. vi. 



Water Snake. 



General color dull brown, exhibiting narrow transverse bands of 

 lighter, margined with dark brown or black ; these bands generally 

 about half a scale in width, and their margins more or less parallel 

 immediately on the back. This is especially the case posteriorly, 

 where they are usually at right angles to the axis of the body ; an- 

 teriorly they are more or less oblique, and widen rapidly towards the 

 abdominal scutellae. Sometimes the general brown hue is so predomi- 

 nant as to render the transverse marks more or less obsolete, and the 

 general tint then appears uniform above. The abdomen is always 

 dull yellowish, each scutella with large blotches of light brown, 

 margined with black. 



