Parasite

{par’ -ahs it) [ rcapd, near; alrog, food]. I. An animal or vegetable living upon or within another organism, termed the host. The most important cla es of animal parasites of man are the following: (A) Protozoa, unicellular organisms, as the Plasmodium mal arise; the Amoeba col i. (B) Metazoa, multicellular organisms, as (a) The Vermes, or worms, including the Trematodes, the most important of which are the Distomas; the Cestodes, Taeniae or tape-worms, including Taenia solium, Taenia mediocanellata or saginata, Taenia echinococcus, and Bothriocephalus lat us; the Nematodes, comprising Ascaris, Oxyuris, Anchylostomum, Filaria, Trichina, and Trichocephalus; (b) the Arthropod a, including the itch-mite, louse, flea, etc. The vegetable parasites are the bacteria and fungi, q. v. 2. In teratology, a fetus or fetal parts attached to or included in another fetus. 479