230 NATURE’S CRAFTSMEN 
the secret of the pebbles yielded into his hand— 
a nice fat caddis worm. 
“ You see,” observed Uncle John, “ self-pres¬ 
ervation warned him to withdraw into his strong¬ 
hold when he was snatched up so rudely. Ordi¬ 
narily he keeps his head and front legs sticking 
out his door, the latter being used as paddles, and 
in this manner he tows his little house-boat along. 
Being white, his person merely sparkles like a 
tiny point of light, and he is all unobserved by 
human eyes, but not thus easily does he pass 
among his neighbors. Always as he sails slowly 
about fishing for a living, he must keep a wary 
eye out for the foes who fain would make a meal 
of him. 
“ Many of the caddis worm tribe spin webs as 
the spiders do to trap their prey. These web 
nets are slung across an opening between two 
stones, and open up-stream. Here tiny minnows 
and other water prizes are taken before they so 
much as guess their danger. Not a few of the 
house-boat builders, however, are almost entirely 
vegetarians. They feed upon the foliage of the 
water plants. If you keep your eyes open this 
afternoon, it is just possible that you may chance 
upon one of these interesting little specimens la¬ 
boriously towing its boat after it as it climbs up a 
plant stem. It will browse about a bit, and sun 
itself, then drop quietly back into the water. 
