1 10 Species of North American Tortoises. 



tail short, striped with yellow. Eyes yellow, with a broad 

 black stripe through the middle. Feet palmate, five-toed: 

 claws 5-4. 



Plates of the margin twenty-five ; of the sternum twelve. 



Length ten inches ; height three inches. 



a. Shell more gibbous, more distinctly carinate, with two re- 

 markable prominent tubercles, on the second and third verte- 

 bral plates, smooth, except a few concentric striae on the 

 lateral plates, and some diverging ruga3 on the others : colour 

 cinereous brown with a few irregular marks of paler, the keel 

 and fore-part of the vertebral tubercles more or less black ; 

 lateral plates with a dusky spot more or less distinct on the hind 

 part of each ; marginal plates outwardly edged with yellow, and 

 with each a dusky spot on the hinder part, where it joins the 

 next. First vertebral plate the smallest and narrowest, much 

 elevated in the middle, somewhat urceolate, pentagonal, the 

 acute angle in front, and very sharp, the second, third and fourth 

 hexagonal, the fifth three-sided, the anterior face curved, the 

 two others posterior and straight ; first lateral plate six-sided, 

 second and third five-sided, the fourth quadrangular ; interme- 

 diate lateral plate small, oblong, wider and deeply emarginate 

 behind, so as to receive the acute and projecting angle of the 

 first vertebral plate, all the rest quadrangular ; the exterior and 

 posterior angle of the two first projecting beyond the rest, and 

 each other, the eighth, ninth, tenth, eleventh and twelfth wider 

 and spreading, projecting like the two first, the eighth, ninth 

 and tenth slightly toothed, the eleventh and twelfth very much 

 so, so that the posterior margin of the shell is deeply serrate 

 with eight or ten teeth on each side. Sternum deeply emar- 

 ginate behind, and with the lateral plates beneath yellow ; 

 scapular plates rather small, triangular, with a small projection 

 at the exterior angle directed forwards ; brachial plates trian- 

 gular, with the apices truncate ; pectoral plates oblong ; abdo- 

 minal and femoral nearly square, the anterior sides of the latter 

 oblique ; caudal plates nearly square ; marginal plates beneath 



