162 
The Cure of Piroplasmosis 
In the following signs, the brackets ( ) represent the corpuscles which 
include the parasites. Thus : 
The sign stands for a corpuscle harbouring: 
(P) 1 pyriform parasite. 
(O) 1 usually round, at times irregular or amoeboid, parasite. 
(PP) 2 pyriform parasites. 
(00) 2 rounded parasites. 
(PPPP) 4 pyriform parasites, usually including types like (PPO), which are rarer, 
and also the still rarer higher numbers of parasites in a corpuscle. 
(PPO) 2 pyriform and one rounded parasite. 
(D) 1 dividing form. 
(DD) 2 dividing forms. 
The abbreviation r.b.c. in the protocols stands for red blood 
corpuscle. 
The enumeration of parasites in untreated dogs. 
As stated in the previous section, an enumeration of the different 
forms of parasites soon revealed the fact that certain forms prevail 
numerically above others. We soon found, that for practical purposes 
other forms could be safely ignored. Thus, an occasional corpuscle 
might contain more than four pyriform parasites (PPPP), but these 
corpuscles were present in very small numbers in the peripheral cir¬ 
culation, and could, in consequence, be included under the heading of 
“ four or more ” parasites in a corpuscle. Similarly, two pyriforms and 
one rounded parasite (PPO) in a corpuscle could usually be included 
in this category, for we know that the rounded parasites in such 
a corpuscle may at times multiply by the “ budding ” process, described 
by Nuttall and Graham-Smith, and give rise to an additional pair of 
pyriform parasites. In one case only, that of Dog 10, did the type (PPO) 
occur in considerable numbers (9°/o) in blood films made at autopsy. 
When about 200 infected corpuscles are counted and classified 
according to the* forms of parasites which they contain, the forms (P), 
(D), (00), (PPPP), may frequently not be encountered. At times they 
are more numerous. The (0) and (PP) are always present in greater 
numbers. Thus, by referring to the protocols, it will be seen that 
parasites of the type 
(PP) may constitute 30—68 % 
( 0 ) 
(PPPP) 
(D) 
(P) 
29 
64 % 
0 - 20 % 
0-7% 
0-6 % 
of the infected corpuscles in untreated 
dogs at various stages of the disease. 
