504 H. B. FANTHAM. 



belonging to the order Acy stosporea^ on account ot' its 

 simple body form, and to the genus Piroplasma on account 

 of its ovoid or pyrifoi'm shape and simple fission in schizo- 

 gony. Since it occurs in the white rat and is apparently con- 

 fined to rats, I have proposed the new specific name muris. 



The other well-authenticated species of Piroplasma- 

 (Patton, 1895), as mentioned by Laveran (23) and others, 

 are — 



(1) P. bigemiuum (SmithandKilborne, 1893), the parasite 

 of Texas fever in the Bovidte, which has since been observed 

 in most parts of the world. This species is sometimes called 

 P. bo vis (as by Nuttall [40], and Stephens and Christophers 

 [47]). The correct name of the species is doubtful. Judging 

 from the illustrations of the relative sizes of the parasite 

 and its corpuscle host, as figured by Smith and Kilborne 



(46) in cases from Texas, and by Stephens and Christophers 



(47) in cases from Madras, there would seem to be more 

 than one species. Lignieres (1900) also thought there were 

 two species of P. bigeminum (P. bo vis) in Ax"gentina, and 

 Nuttall (40) has emphasised this point. Some authorities, 

 again, apply the name P. bo vis to the parasite of bovine 

 haomoglobinuria in Europe, spread by Ixodes reduvius, 

 separating it from P. bigemiuum, which latter name is 

 restricted to the parasite of Texas Fever (Tristeza, Red- 

 water). 



(2) P. parvum, separated by Theiler (48,49) in 1904, as a 

 distinct species from the former, and found in Bovida) suffer- 

 ing from East Coast Fever (Tropical Bovine Piroplasmosis, 

 " llhodesian Redwater " [16, 18, 19, 20]). It also occurs in 

 Transcaucasia (11). 



(3) P. canis (Plana and Gulli-Valerio, 1895), occurring in 



* The distinction between tlic sub-orders Acystosporea and Hxniosporca 

 is not now so sliarp as formerly considered, since t.lie discovery of intermediate 

 hosts in the case of several Ilamogregarines, and the finding of llajmo- 

 gregarina gerbilli by Christophers in a mammal. 



^ The synonymy of the generic name "Piroplasma" is given by Miucliin 

 (37, p. 2G9). Probably the strictly correct name, by priority, is "Babesia," 

 though the name "Piroplasma" is almost universally used. 



