210 REPTILES OF MASSACHUSETTS. 



mon name of wood tortoise. Its usual length is from six to 

 eight inches. The iipj er shell is composed of five dorsal, eight 

 lateral, and twenty-five marginal plates ; these plates are of a 

 greenish brown color, strongly marked with concentric and 

 radiating stria3. A dorsal ridge is formed by the convex por- 

 tion of the superior plates. Sternum composed of twelve yel- 

 low plates, having upon their posterior lateral margins, a large 

 black spot. All the under portion of the legs, neck and tail, 

 is red. 



Young specimens exhibit a very rough upper shell, produced 

 by the prolongations of the posterior angles of the plates. 



This species was erroneously considered by Say, as synony- 

 mous with the '' scahj'a,^^ Lin. ; and as such, he catalogued it the 

 4th Vol. J. A. N. S. 



Sternothaerus. Bell. 



Generic characters. Head subquadrangular, pyramidal, 

 covered in front ivith a single plate; warts on the chin ; mar- 

 ginal plates, twenty-three ; sternum cruciform, bivalve, ante- 

 rior valve only moveable ; supplemental plates contiguous, plac- 

 ed on the sterno-costal suture ; anterior extremity ivith five 

 nails, posterior with four. 



S. odoratus. The mud Tortoise. 



Ann. Lye. Nat. Hist. N. Y. vol. iii. p. V22. 

 Harl. Med. and Phys. Res. p. 1.5G. 

 Dum. et Bibr. Hist. Nat. des Rept. torn. ii. p. 358. 

 N. A. Herpet. v. iii. p. 29, et fig. 



Shell oblong, convex, somewhat carinated on the dorsal 

 ridge ; of a brownish color, irregularly blotched with darker 

 spots. 



The first vertebral plate is triangular, the next three hexa- 

 gonal, the last pentagonal. There are four lateral plates ; the 

 first of which is quadrangular, the remainder are pentagonal. 

 The marginal plates, twenty-three in number, are small, gen- 



