HOW ANIMALS EAT. 5p 
pairs of horny jaws, which open sidewise, one above and 
the other below the oral orifice. The upper pair are called 
mandibles; the lower, maxille. The former are armed 
with sharp teeth, or with cutting edges, and sometimes are 
fitted, like the molars of quadrupeds, to grind the food. 
The maxillz are similar, but smaller, and in some Insects 
have appendages called palpi, or feelers, which not only 
select, but hold, the food steady while they are divided by 
the mandibles and maxilla: such appendages represent a 
third pair of jaws. The Mantis seizes its prey with its 
long fore legs, crushes it between its thighs, which are 
armed with spines, and then delivers it up to the jaws for 
mastication. All Articulates move their jaws horizontally. 
The back-boned animals generally apprehend food by 
means of their jaws, of which there are two, moving ver- 
tically. The toothless Sturgeon draws in its prey by pow- 
erful suction. The Hag-fish has a single tooth, which it 
plunges into the sides of its victim, and, thus securing a 
firm hold, bores its way into the flesh by means of its saw- 
like tongue. But Fishes are usually well provided with 
teeth, which, being sharp and curving inward, are strictly 
prehensile. The fins and tongue are not prehensile. A 
mouth with horny jaws, as in the Turtles, or bristling with 
teeth, as in the Crocodile, is the only means possessed by 
nearly all Reptiles for securing food. The Toad, Frog, 
and Chameleon capture insects by darting out the tongue, 
which is tipped with glutinous saliva. The constricting 
serpents (Boas) crush their prey in their coils. before swal- 
lowing ; and the venomons Snakes have a poison- fang. 
No Reptile has prehensile lips. All Birds use their tooth- 
less beaks in procuring food, but birds of prey also seize 
with their talons, and Woodpeckers, Hummers, and Par- 
rots with their tongues. The beak varies greatly in shape, 
being a hook in the Eagle, a probe in the Woodpecker, and 
a shovel in the Duck. 
