LECTURE VII. 
IS 
their very large and long fin-shaped feet, in which 
are inclosed the bones of the toes ; the first and se^ 
cond alone on each foot being furnished with 
visible or projecting claws ; the rest not appearing 
beyond the edge. The shield, as in the Land 
Tortoises, consists of a strong bony covering, in 
which are imbedded the ribs, and which is coated 
externally with hard, horny plates ; in one or two 
species much thicker than the horny covering 
or epidermis of the land Tortoises. There is 
however one species of Turtle, and that the 
largest of all others, which instead of a strong 
horny covering, has one of a leathery consistence, 
marked over the whole surface into small angu- 
lar subdivisions which do not take away from 
the general smoothness of the whole : along the 
whole upper part run five prominent ribs or lines, 
while the under parts of the animal are bare, 
or destitute of any lower shell, so that this animal 
might form a distinct genus from the rest of the 
Turtle tribe. Its colour is olive-brown, and its 
size so great that it has been seen of the length 
of eight feet, and of the weight of a thousand 
pounds. It has been sometimes taken both on 
the coast of France and England. It is found 
