HISTORY AND HABITS OT THE TESTUDINATA. 
XX11J 
prey, if it be motionless or nearly so, they usually creep towards it with great 
caution, stretching the neck slowly till the month is within a short distance, 
and then seizing it by a sudden snapping motion of the jaws. I had an 
individual specimen of Emys decussata in my possession, which, whenever it 
was about to take food, stretched out the two anterior feet, one on each side 
of the head, and with the palms outwards. These were held in the same 
position for some moments, but agitated with a vibratory motion, after which 
the head was suddenly darted forwards on the prey. This curious manoeuvre 
was repeated as often as a morsel of meat was held near him; but I never ob¬ 
served a similar habit in any other tortoise of this or any other species. In 
pursuing their prey however, when swimming, a greater degree of rapidity is 
of course necessary. I have seen a common fresh-water tortoise, Emys lutaria , 
pursue a frog in a large vessel of water with considerable rapidity, seize it by 
the belly, and tear it to pieces in a very short space of time. These animals 
may be very easily kept during the summer in a small pond or reservoir of 
water, by feeding them with pieces of raw lean beef, if living frogs, fish, or 
worms cannot be readily obtained. They will also feed on the intestines of 
fowls, and on almost any other animal substance. 
The force and tenacity with which the carnivorous Testudinata seize and 
hold their food is very great. They may in fact, in some cases, be easily 
caught by allowing them to seize a piece of meat attached to a string, and 
then drawing it quickly out of the water. 
The habits of Chelydra serpentina are those of extreme voracity. Endowed 
with great strength, and astonishing rapidity and. force in the movements of 
its limbs and neck, it is enabled to pursue, seize and tear in pieces, fish of no 
inconsiderable size, and the young of aquatic birds which swim on the surface 
of the lakes in which it abounds. 
It is said also to conceal itself in the mud, by which means it escapes the 
observation of the animals which it makes its prey, till they come within its 
reach. In this circumstance, as well as in the sudden snapping motion by 
which the species just mentioned seizes its food, the whole of the Trionychidce 
probably resemble it. The flatness of the body and the soft flexible structure 
of its broad coriaceous margin peculiarly adapt them for concealment in the 
