Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.


The Protozoa, or one-celled animals (nearly all microscopic).

The mode of feeding of the sponge is very similar to that of the protozoa.

Two things must be noticed before we leave the subject of the Protozoa.

The animals which are higher in structure than the Protozoa, viz.

The first grade includes only the Protozoa, or unicellular animals.

These protozoa possess, as it were, only negative properties.

The invertebrata are divided into sub-kingdoms, of which the protozoa form one.

In no case were the protozoa recovered from the stomach alive.

A more tangible example of the Protozoa are the Foraminifera.

It is thus evident that the Protozoa is an ancient group of animals.