TRICHOPTERA. 
IS 7 
Family PHRYGANEIM: (Phryg-a-ne'i-das). 
The Caddice-flies or Caddice-worms. 
The young naturalist loves to lie face downward on the 
bank of a brook, and, with shaded eyes, watch the busy life 
that goes on there. Among the astonishing things he sees 
are little bundles of sticks or masses of stones moving about 
the bottom of a quiet pool as if they were alive ; and yet if 
he takes them out they seem dead enough. But when 
he pulls them apart he finds that each is a tube lined 
with silk within which a whitish larva lives. This larva, 
when it wishes to move, puts out the front part of its body, 
so that it can creep with its legs over the bottom of the 
stream, or climb up and down water-plants, dragging its 
house along: after it. When molested it draws back into its 
tube, and is safe. Larvae of this sort are called Caddice- 
worms; and the adult insects are known as Caddice-flies. 
There are very many species of Caddice-worms ; and each 
species makes a particular kind of tube. Some Caddice- 
worms are carpenters, building their houses of straws or 
sticks. These are usu¬ 
ally placed lengthwise 
the body (Fig. 226); 
but certain species that 
Fig. 226. make their houses chief¬ 
ly of straws fasten the straws crosswise like the logs of a 
log-house (Fig. 227). These log-house builders 
often have the curious habit of decorating their 
houses by fastening snail-shells to the outside. 
And strangely enough they do not always take 
empty shells for this purpose; we have found 
shells containing living snails securely fastened Fig - 22 7 - 
to the outside of the house of a Caddice-worm. In this case 
the snail was afforded comparatively rapid transportation 
whether it desired it or not. Fortunately the species that 
