546 Veterinary Medicine. 



vaded by the parasite, nor were the corpuscles lessened in 

 number. In the afEected cattle, the red cells were reduced from 

 the normal 7,000,000 per cubic mm. to 1,800,000 and even lower 

 in some cases. 



The Piroplasma Bigeminum passes through a series of forms in 

 the blood. Theobald Smith found in the red globule and attached 

 to its margin a. pale round body o.Sf- in diameter, and staining 

 freely in alkaline methylene blue and other basic anilin dyes and 

 in hcematoxylin , but not in acid coloring fluids. These he found 

 in the red globules in acute caises, often in company with the pear- 

 shaped bodies, and usually in the absence of the piriform bodies 

 in chronic cases, in non-fatal relapses, in cases occurring in cooler 

 weather, (late autumn or early winter) and in immune southern 

 cattle. The red cells containing these rounded organisms were 

 not crenated nor distorted, though 50 per cent, of them might 

 contain the parasite. He looked on these as the earlier stage of 

 the organism which later developed into the piriform body, by 

 segmentation of its substance. The piriform or spindle-shaped 

 bodies were usually found in pairs connected at their pointed ends 

 by a filament and extending across nearly the whole breadth of 

 the red globule. Free microorganisms , pear-shaped or round, he 

 failed to find in the blood of the large vessels, but saw them 

 only in the cardiac capillaries and especially in the kidneys. 

 In some cases the dim remnant of the disintegrated blood globule 

 could still be detected around the parasite. 



L,averan and NicoUe, examining the blood of Italian cases by 

 fixing and staining, found the two forms, round or oval, and piri- 

 form, and claimed that the first passed into the second by seg- 

 mentation. 



I^ignieres working in Buenos Ayres with the most ample op- 

 portunity as regards fresh material and authority to use it, 

 watched the successive changes in the living organisms, and 

 reached further conclusions. He diluted the blood with a 7 per 

 cent, salt .solution, or with ox serum or both, until the globules 

 stood apart in the field. The blood can be kept under observa- 

 tion for days under a cover-glass luted with sterile paraffin, and 

 the changes clearly traced. Securing the blood from a subject 

 having a great abundance of infected globules (usually at the 

 height of the haeraoglobinuria) he found mainly i\\Q piriform para- 



