168 LIFE AND HER CHILDREN. 
on his strong muscular limbs ; but seizing them in 
his powerful claws he cracks their shells if they have 
any, and tears their flesh to pieces, tucking it greedily 
into his mouth, which looks as if it were in the 
middle of his body. He even makes no difficulty of 
breaking the shell of one of his own kind and feeding 
upon it from behind, while it in its turn is eating 
some smaller and weaker brother. 
To devour and be devoured seems to be the main 
mission of crabs, and they feed so greedily that we 
shall not be surprised to learn that besides their 
array of outer jaws, they, and many of the other 
Crustacea, have hard teeth in their stomach (j, Fig. 
58) which help to grind down the food. You may 
see these teeth well in the stomach of the lobster, 
where children often call them the " lady in her 
chair." 
At first sight it is difficult to understand how a 
crab can belong to the ringed animals, but if you 
lift up the tail, which is tucked under the body, 
you will see that this is ringed like the abdomen of 
the prawn, and if you break off the legs carefully 
you will find under them the finger-like gills, showing 
that the body of the crab answers to the head and 
thorax of the prawn, only that the shield over its 
back is much broader, and is fastened down firmly 
at the sides, while the tail is tucked under instead of 
standing out. 
Moreover, if you could see the crab when he is 
first hatched from the egg (i, Fig. 59) you would see 
his tail stretched out and jointed as distinctly as that 
of the prawn, and at this time, with his flat eyes and a 
curious spine sticking out of his back, he is as unlike 
