222 THE OPEN BOOK OF NATURE 
some water-plant. It can readily detach itself from 
any site it occupies, and travel about by looping its 
body, somewhat after the manner of a caterpillar, 
using its foot and proboscis in the operation, in the 
place of ordinary legs. This animal is found in 
many situations—ponds, gutters, puddles, and even 
amongst conferva on damp walls. 
One of the most marvellous 
Ne, sity, = -of the several kinds of Roti- 
= : 3 fers is the Melicerta. You 
have seen the little tubes 
made of bits of rushes, stick, 
fibre, seeds, grains of sand, 
and other materials which 
are occupied by the clever 
little larve of the Caddis 
Fly; and I have no doubt 
you have often found on the 
seashore the wonderful little 
tubes, made of cemented shell 
particles and grit, in which 
the worms called Terebella 
make their homes. Now, the 
Melicerta, which is not more 
than a fifteenth of an inch in 
length, is a builder equally as clever as the Caddis 
Worm or the Terebella. This Rotifer finds a suit- 
able site on the leaf or stem of some pond plant, on 
which it erects its permanent home. It makes very 
tiny round pellets, which it lays around itself in a 
small circle. Pellet after pellet is made, laid, and 
cemented to the others, until a tower-like tube is 
built. In this tube the Melicerta resides, like a 
Fig. 58.—MEicerta. 
