Thus, to begin with, the animal pedigree is divided into two very distinct grades, the Protozoa and the Metazoa.
We have analogies to this in the two nuclei of some of the protozoa, the one being solely for the purpose of propagation, the other being associated with the functional activities of the cell.
Anatomic, Berlin, 1845) as that of a primary division of animals, the others recognized in that treatise being Protozoa, Zoophyta, Vermes, Mollusca and Vertebrata.
Linnaeus applied the Latin term Vermes to the modern zoological divisions Mollusca, Coelentera, Protozoa, Tunicata, Echinoderma (qq.v.), as well as to those forms which more modern zoologists have recognized as worms. As a matter of convenience the term Vermes or Vermidea is still employed, for instance in the International Catalogue of Zoological Literature and the Zoological Record, to cover a number of wormlike animals.
GASTROTRICHA, a small group of fairly uniform animals which live among Rotifers and Protozoa at the bottom of ponds and marshes, hiding amongst the recesses of the algae and sphagnum and other fresh-water plants and eating organic debris and Infusoria.