Hæmatozoa

Hæmatozoa (Gr. haima, 'blood,' and zōōn, 'an animal'), parasites occurring in the blood. (a) Some Gregarines (q.v.) live in the blood-corpules of frogs, reptiles, and birds. (b) A few Nematodes occur in the vascular system—e.g. Filaria immitis, in the heart of the dog; Strongylus armatus, causing abdominal anæmisia, in horse and ass; Filaria sanguinis hominis, which in Australia, China, India, Egypt, and Brazil occurs in man, the sexual female in the lymph glands causing Elephantiasis (q.v.), &c., the embryos circulating in the blood and causing hæmaturia, &c., while the larval asexual stages occur within a mosquito. (c) A very important blood parasite among Trematodes is Bilharzia (q.v.), occurring in Africa, in the blood-vessels of the bladder, mesentery, and portal system of man. See BILHARZIA, GREGARINE, NEMATODE, PARASITISM; also Lenekart's Parasites of Man, trans. by W. E. Hoyle (Edin. 1886).