HOW ANIMALS EAT. 
57 
The mouth of the Cuttle-fish is the most elevated type 
below that of the Fishes. A broad circular lip nearly 
conceals a pair of strong horny mandibles, not unlike the 
beak of a parrot, but reversed, the upper mandible being 
the shorter of the two, and the jaws, which are cartilagi¬ 
nous, are imbedded in a mass of muscles, and move ver¬ 
tically. Between them is a fleshy tongue covered with 
teeth. 
The parasitic Worms, living within or on the outside 
of other animals, generally have a sucker at one end or 
underneath, serving simply for attachment, and another 
which is perforated. The latter is a true suctorial mouth, 
being the sole inlet of food. It is often surrounded with 
booklets or teeth, which serve both to scarify the victim 
and secure a firm hold. In the Leech, the mouth is a 
triangular opening with thick lips, the upper one pro¬ 
longed, and with three jaws. In many Worms it is a 
fleshy tube, which can be drawn in or extended, like the 
eye-stalks of the Snail, and contains a dental apparatus 
inside (Fig. 17). 
Millepedes and Centipedes have two lateral jaws and a 
four-lobed lip. 
In Lobsters and Crabs the mouth is situated underneath 
the head, arid consists of a soft upper lip, then a pair of 
upper jaws provided with a short feeler, below which is a 
thin bifid lower lip ; then follow two pairs of membranous 
under jaws, which are lobed and hairy; and next, three 
pairs of foot-jaws (Fig. 250). The Horse-shoe Crab has 
no special jaws, the thighs answering the purpose. The 
Barnacle has a prominent mouth, with three pairs of rudi¬ 
mentary jaws. 
With few exceptions, the mouths of Insects in the lar¬ 
val state are fitted only for biting, the two jaws being 
horny shears. But in the winged, or perfect, state, Insects 
may be divided into the masticating (as the Beetle) and 
