HOUSE-BOAT BUILDERS 131 
altogether unselfish one. He knows these tiny 
morsels will be delicious eating by and by. So 
he throws a thin, colorless covering over them, 
which protects them like a capsule. And there 
they spend the winter, using him as a sort of 
house-boat, and growing in their odd transparent 
nest as thriftily as the baby moth does in its silken 
cocoon. 
“ When the tiny creatures have come to look 
just like their mother in everything but size, they 
leave their good friend and set out to take 
their chances in the water world again. This 
time they are more able to fend for themselves. 
Indeed, they are so far grown up that they begin 
at once to look about for a location to settle down 
in, where they can begin to fashion a house-boat 
of their own. Moreover, the muddier the site the 
better! The sea-going cousins of the species have 
long siphons which they can shorten or lengthen 
at will. They are fond of burrowing deep in wet 
sand, with only just their siphon mouths sticking 
out to glean food from the tides as they wash 
above them. 
“ As our friend works, she is fond of leaving 
her doors wide open. And, as you may imagine, 
sometimes strange things come wandering in,— 
a frog’s foot, a bird’s toe, or perchance the toe of 
a boy. Then snap goes the door, and you may 
guess what happens! Often a few grains of sand 
