Theileria annulata (Dschunkowsky and Luhs) occurs in cattle in Transcaucasia.

A Theileria (T. stordii) has been found in a gazelle (França, 1912).

Genus. Anaplasma, Theiler, 1910.

This genus[221] may be mentioned here. The organisms included therein are, according to Theiler, coccus-like, consisting of chromatin, and are devoid of cytoplasm. They occur in the red blood corpuscles of cattle, causing a disease characterized by destruction of red cells, fever and anæmia, but with yellow urine. The disease is tick transmitted. The bodies now called Anaplasma marginale were formerly described as marginal points. They multiply by simple fission. They are said by Theiler to cause gall-sickness in cattle in South Africa. Some authors doubt whether these bodies are organismal.

Genus. Paraplasma, Seidelin, 1911.

Under this generic name Seidelin described certain bodies found by him in cases of yellow fever in 1909. The type species is P. flavigenum,[222] and is claimed by Seidelin to be the causal agent of yellow fever.

Paraplasma flavigenum occurs in the early days of the disease as small chromatin granules with or without a faint trace of cytoplasm. The bodies are usually intracorpuscular. Also, somewhat larger forms, with distinct cytoplasm, are seen in small numbers. During the later days of the disease still larger forms are found, and these occur also in sections of organs (e.g., kidney) made post-mortem. Some of these larger forms are perhaps schizonts. In the second period of the disease possible micro- and macro-gametes may be found, some of which are extracorpuscular. Some small free bodies have been seen. Recently schizogony has been stated to occur in the lungs, and it is said that guinea-pigs can be inoculated with Paraplasma flavigenum, and show yellow pigment in the spleen.

Seidelin places Paraplasma in the Babesiidæ, with resemblances more particularly to Theileria. V. Schilling-Torgau and Agramonte have criticized these findings; the former considers them to be the resultant of certain blood conditions.

P. subflavigenum was found by Seidelin in 1912 in a man suffering from an unclassified fever in Mexico.

Further, it is now known that a Paraplasma occurs naturally in guinea-pigs. More researches are needed on these matters, as some writers (e.g., Wenyon and Low) claim that the bodies are not organismal.