369 THE WORLD OF THE SEA. 
The sea turtles have jaws which are destitute of teeth, their 
gums are of a hard, horny material, sharp at the edges, like the 
beaks of the birds of prey. The utility of this form of mouth will 
be at once recognised, when we remember that the turtles feed on 
submarine vegetables; the fronds of the algae would be more easily 
severed by these scissor-like jaws, than even by teeth. Some of 
the Chelonia are not entirely herbivorous, for they eat mollusks, 
and also cuttle-fish, and other soft, pulpy creatures. 
From the clumsy appearance of the turtle, we might well 
conclude that the motions of the creature were slow and lazy; but 
this is by no means the case; when in its native element, its arms 
are powerful oars, and with their assistance it can glide easily and 
swiftly through the water. The turtle can remain under water a 
THE HEAD OF THE TURTLE. 
long time, the orifice of its nasal canal, through which the air enters 
to the lungs, is covered by a lump of flesh, which acts as a valve, 
and at the will of the creature can hermetically seal the orifice, 
thus effectually preventing the entrance of any water, or the exit 
of the air, 
Often, hundreds of miles away from land, a number of turtles 
may be seen floating on the surface of the sea, perfectly motionless ; 
they are asleep, more gently rocked than even an infant in its 
nurse's arms. Although protected to a great extent by the horny 
covering of their carapace, yet the turtles are not invulnerable, 
neither when attacked are they capable of resistance, but are at 
the utter mercy of their foe. To compensate for this, they are 
endued with a peculiar tenacity of life, and a turtle will show signs 
of sensibility, even after it has been decapitated. 
These creatures are oviparous, producing their young by eggs. 
At the time of depositing her eggs, the female comes on land, and 
