stomach is called the pyloric end, and it is made inside like a sieve or strainer. The sides are stuffed out in the centre like cushions, and quite covered with hairs (Fig. 25). Let us see why. Pylorus means gate-keeper. It protects or guards the intestine from all intruders,

such as big pieces of meat and hard bodies. None but the finest particles can pass through the strainer, and hence this pylorus is a very good gate-keeper. The intestine does not go wandering about in the body like the mussel's, but passes straight back (Fig. 22), and ends at the