386 MICROBIOLOGY 



heart muscle and kidney. They were, however, much in evi- 

 dence in films from the peripheral circulation. The presence 

 of this organism is generally considered diagnostic of Texas 

 fever. It does not appear as yet to have been cultivated on 

 artificial media. 



PIROPLASMA OVIS. 



Synonym. Babesia ovis Starcovici. 



Place in nature. Babes found this organism to be the 

 cause of the disease known as "carceag" or ictero-hemoglobi- 

 nuria of sheep in Roumania. It was later described by 

 Bonome 7 in an epizootic of a similar kind in Italy. This 

 parasite is described as being very similar to that of Piro- 

 plasma bigeminum except that it is somewhat smaller. 



PIROPLASMA EQUI LAVERAN. 



Place in nature. This organism was discovered by Grugli- 

 elmi 1 in horses. It is the cause of a febrile disease (Piroplas- 

 mosis) accompanied by. an acute anemia. It was found by 

 Theiler 2 that it could' be inoculated from immune horses into 

 mules and from mules into susceptible horses. The organisms 

 are readily found in the blood of the horse during the febrile 

 stage of the disease. Theiler 3 showed that they were trans- 

 mitted from horse to horse by means of Rhipicephalus everst. 

 It does not seem to have been reported in the United States. 



Morphology. Piroplasma equi as found in infected blood 

 appears as spherical or elongated, oval or rarely- pyriform 

 bodies. They are nearly always within red corpuscles. It is 

 riot common to find them -free in the plasma. The parasites are 

 from 0.5 to 2.5 //, in diameter, the most common being 1.0 to 

 1.5 /*. The following forms of the parasite are described by 



7 Bonome. Virchow's Archiv, Bd. CXXXIX (1895) p. 1. 



1 Guglielmi. La clinica veterinaria, 1899, p. 220. 



2 Theiler. Ann. Kept, of the Director of Agriculture, Transvaal, 

 1904-1905, p. 94. 



3 Theiler. Schweitzer-Arch, f. Tierheilk., Bd. XLVII (1901) p. 

 ' 253. 



