CISTUDA CAROLINA. 



33 



frequently the eighth, ninth, tenth and eleventh marginal plates, and sometimes 

 the twelfth, are revolute, and form a gutter. 



The sternum is oval, with an entire margin, and consists of two sections, of 

 Avhich the posterior is larger. These sections are joined to the shell and to each 

 other by a ligamento-elastic structure, so that both valves are movable on the 

 same axis, and can be brought in contact with the carapace, and thus conceal the 

 head, neck, extremities and tail of the animal. The gular plates are triangular, 

 with their bases forwards; the brachial and thoracic are quadrilateral, the former 

 the more regularly so; the abdominal are quadrilateral and large; the femoral 

 and sub-caudal plates are triangular, the former with their apices truncate. 



The head is small; the nostrils anterior and closely approximated. The eyes 

 are large; the pupil black, the iris varying from golden to red or grey. The 

 upper jaw has a broad hook, and the lower is furnished with a small one in front. 



The anterior extremities are short, rounded, and covered with large scales in 

 front and smaller behind; there are five fingers, slightly palmated, and each 

 furnished with a short, thick, curved nail. The posterior extremities are rounded 

 above, but flattened at the tarsus, and covered with small scales, having only a 

 few large ones behind; there are five toes, semi-palmated, four only of which are 

 furnished with nails. The tail is very short and thick. 



Colour. In no other tortoise is there such a great variety in the colour and 

 markings of the shell. I have seen more than one hundred living specimens 

 together, and could not select two precisely ahke. Perhaps the most ordinary 

 colour of the shell is yellowish-brown, with spots or stripes of bright yellow; 

 sometimes these are sub-radiating, or even radiating; at others they are disposed 

 without order; occasionally there is an entire vertebral line of bright yellow, but 

 most frequently it is interrupted with black. This arrangement of the colours 

 often gives to the carapace the appearance of tortoise shell. 

 Vol. I.— 5 



