G. H. F. Nuttall and C. Strickland 
67 
Piroplasrna {P. caballi Nuttall 1910) which also occurs in horses 
suffering from “ biliary fever.” As one of our P. caia^h'-infected horses 
was inoculated with N. equi after it had recovered from the clinical 
symptoms produced by the first-named parasite, it will make matters 
clearer to show the course of the experiments in the form appended:— 
NuttaUia eqxd 
Horse I. Inoculated 27. xi. 1909 with blood 
obtained from Sir John McFadyean. 
Parasites appeared 8th day. Horse died 
11th day. 
I 
Horse II. Inoculated 8. xii. 1909 with blood 
from N. equi Horse I. Parasites appeared 
7th and disappeared 22nd day. Horse 
recovered, and is still alive, 27 February, 
1912. 
i 
Horse III. Inoculated 2. viii. 1910 with- 
blood from N. equi Horse II. Parasites 
appeared 10th day. Horse died 20th day. 
’ iV. equi Horse HI is the same animal i 
was carried on from Horse II to III before F. 
Piroplasrna caballi 
Horse I. Inoculated 4. vi. 1910 with blood 
obtained from Dr E. J. Marzinowsky. 
Parasites appeared 15th day. Horse 
died 19th day : 22. vi. 1910. 
I 
—Horse II. Inoculated 22. vi. 1910 from 
P. caballi Horse I. Parasites appeared 
8th day. Horse recovered. (Subsequent¬ 
ly inoculated with N. equO.) 
I 
Horse III. Inoculated 18. vii. 1910. 
Parasites appeared 9th day. Horse died 
19th day. 
,s P. caballi Horse H. The P. caballi strain 
caballi Horse II was inoculated with N. equi. 
I. NUTTALLIA EQUI (Laveran). 
(A) The living parasites. 
Although we spent roundly 200 working hours in the continuous 
study of the living parasite in fresh blood-films maintained at body- 
temperature, the results of our observations can be summarized briefly. 
The following summary is based on the continuous observation, coupled 
with graphic records', carried out on 
Average duratiou of 
observation on each 
parasite in minutes 
41 small and medium-sized parasites ... ... ... 79 
43 medium and large-sized parasites ... ... ... 106 
8 pairs of small and medium-sized parasites ... ... 83 
38 dividing and cross-forms ... ... ... ... 95 
The number of infected corpuscles as compared to uninfected ones 
was small. Thus, in Horse I the number of infected corpuscles did not 
^ The accompanying diagrams are selected from a large series of graphic records. 
