260 THE MIcRoscopPE. 
The Polyzoa are all easily visible to the naked eye, and com- 
mon in shallow water or at the margins of deep ponds. They 
may be found in spring and summer in almost equal profusion, 
at least in the writer’s locality. 
The animals inhabiting the jelly masses or the chitinous 
tubules are timid creatures. When all is well with them, and 
they have no suspicion of lurking danger, a portion of each body 
is protruded into the water and the Polyzoan employs its time 
in searching for food. Light does not 
frighten them, although they live in 
secluded, partially darkened places ; yi- 
brations of the air, provided these can 
be felt, do not affect them; but the 
slightest jarring of the water, the small- 
est wave, or the most delicate ripple 
<A iy terrifies them and they fold together 
eat able. the protruded parts, and like the 
A—Annulus. proverbial flash, lean backward into 
their jelly or their tubules. 
About the only part of the body protruded beyond the orifice 
of the domiciliary cell is the portion called the lophophore. 
This is a circular or horse-shoe shaped region bearing on its upper 
surface one or two rows of long tentacles. These are flexible, 
entirely clothed with vibratile cilia, and each is movable inde- 
pendently of all the others. It is this tentacle-bearing lopho- 
phore that the microcopist sees when he waits until the animals 
have recovered from their fright, and have protruded themselves 
from their cells. They are so graceful in appearance, they add 
so much to the beauty of the animals, that the latter are among 
the most attractive of the larger microscopic and aquatic creatures. 
At the centre of the lophophore a deep depression leads to 
the oral aperture, and the function of the ciliated tentacles is to 
collect the Infusoria and other small creatures upon which the 
Polyzoa feed. The very active cilia produce currents in the 
water that carry the food particles within the circle of the ten- 
tacles which, especially if the morsel is of some size, form them- 
selves into a kind of cage or trap to prevent its escape, and the 
animal then takes care of it in a manner satisfactory to itself. 
It is not the writer’s purpose to describe in detail the struct- 
ure and the habits of our fresh-water Polyzoan forms, but 
