G. H. F. Nutt ALL and C. Strickland 
81 
(C) Comparison of types of parasites encountered in 
different species of Piroplasma. 
A comparison of the different species of Piroplasma in respect to 
the predominant types which are encountered in the peripheral blood, 
only P. pithed being omitted, shows that they all agree fairly well: 
Species % of types encountered 
S’o. of counts averaged 
(each representing 
250 to 500 parasites) 
plasma (P) (0) 
(D) (PP) (OO) (Pi) 
> Reference 
Cahalli 6-5 60-8 
4-8 27-6 — ~ 
N. & S. 
4 
Cahalli 65 
5 30 — — 
N. & S. 
3 
Bovh 00 
11 34 — — 
Nuttall & Graham-Smith 
(1908, p. 139) 
2 
Bovis 54 
6 40 — — 
NuttaU & Hadwen 
(1909, p. 247) 
7 
Bovis 55 
6 39 — — 
Nuttall & Hadwen 
.-^-, 
(1909, p. 244) 
7 
Canis o'O 45-0 
0-7 43 1 4 
Nuttall (1910, p. 423) 
7 
Canis 0‘6 54-0 
3 41 0‘6 0'7 Nuttall & Hadwen 
(1909, p. 171) 
7 
If we gi’oup the numbers in two columns according 
as the infected 
corpuscles contain 
a single parasite 
or two or more parasites we obtain 
the following: 
Corpuscles containing 
Single 
parasites 
Two or more 
parasites 
No. of counts 
averaged 
F. caballi 
71 
29 
7 
P. bovis 
61 
39 
7 
P. canis 
54 
42 
14 
In the above table the forms (P), (0) and (D) are reckoned as one 
parasite. The results of the enumerations in the case of Nuttallia equi 
are totally different, even when we 
inelude the dividing 
or cross-forms 
in the second column ; thus we obtain : 
Corpuscles containing 
Single 
parasites 
Two or more 
parasites and (D)s 
No. of counts 
averaged 
N. equi 
96 
4 
7 
N. equi 
95 
5 
19 
These counts. 
therefore, indicate, apart from the 
differences in 
morphology, that Piroplasma and 
Nuttallia are distinct parasites. 
1 The signs (00) and (P 4 ) indicate corpuscles containing respectively tvro rounded and 
four or more piriform parasites. 
Parasitology v 
6 
