THE TORTOISE. 101 



deposits in it about a hundred and fifty or two hundred 

 eggs, scrapes the sand back again, and goes off to the sea. 



Here, then, we have a case where the machinery 

 which enables the creature to swim in the sea, also 

 enables it to make short journeys on land, and to pro- 

 vide for its future young. The animal is a trespasser 

 upon the domain of water, and not a denizen of it. 



It has already been mentioned that some of these 

 reptiles are vegetable feeders, while others are car- 

 nivorous. Yet, there is very little difference in the 

 structure of their mouths; and for the following 

 reason. Whether it eat animal or vegetable sub- 

 stances, it does not masticate its food, but only bites 

 or tears it into pieces, small enough for it to swallow. 



Both jaws are edged with a very strong, horny plate, 

 nearly as sharp as a knife, and more or less waved, so 

 as to produce a " drawing-cut,^ as swordsmen say, 

 when the jaws are closed. Some of these creatures 

 are much dreaded for their power of jaw ; for they 

 have been known to take off a man's finger at a single 

 bite, or to sever in the same way an ordinary walking- 

 stick. The lower jaw is rather smaller than the upper, 

 and when the mouth is closed, the sharp edges of the 

 upper jaw overlap those of the lower, so that they act 

 just like a pair of shears. 



Armed with these powerful instruments, the turtles 

 can either crop the marine vegetation on which they 

 feed, or even tear to pieces animal substances. Some 

 species, such as the Loggerhead Turtle, which has just 

 been mentioned, live almost entirely upon molluscs, 

 their shear-like jaws crushing shells of considerable 

 size and great hardness. 



