HOW ANIMALS EAT. 
55 
make use of their feet in securing prey, all four limbs be¬ 
ing furnished with curved retractile claws; but the food 
is conveyed into the mouth by 
the movement of the head and 
jaws. Man and the Monkeys em¬ 
ploy the hand in bringing food 
to the mouth, and the lips and 
tongue in taking it into the cavi¬ 
ty. The thumb on the human 
hand is longer and more perfect 
than that of the Apes and Mon¬ 
keys; but the foot of the latter 
is also prehensile. 
2. The Mouths of Animals. 
—In the Parasites, as the Tape¬ 
worm, which absorb nourishment 
through the skin, and Insects, as 
the May-fly and Bot-fly, wdiich do fig. i9.-Arm of the Thumbless 
all their eating in the larval state, 
the mouth is either wanting or rudimentary. The Amoeba, 
also, has no mouth proper, its food passing through the 
firmer outside part of the bit of protoplasm which consti¬ 
tutes its body. Mouth and anus are thus extemporized, 
the opening closing as soon as the food or excrement has 
passed through. 
In the Infusoria the mouth is a round or oval opening 
leading through the cuticle and outer layer of protoplasm 
to the interior of the single cell which makes their body. 
It is usually bordered with cilia, and situated on the side 
or at one end of the animal. 
An elliptical or quadrangular orifice, surrounded with 
tentacles, and leading directly to the stomach, is the ordi¬ 
nary mouth of the Polyps and Jelly-fishes. In those 
which are fixed, as the Actinia, Coral, and Hydra, the 
mouth looks upward or downward, according to the posi¬ 
tion in which the animal is attached (Figs. 38,191, 207): 
