310 
Trypanosoma lewisi 
larger percentage of rats are infected during the months June to 
October than during the remaining months of the year. His per¬ 
centage figures of infected animals ( M. decumanus ) for each month 
from May 1894, to April 1895 are reproduced in Table IY ; the total 
number of animals examined during this year was 2102. We have 
+ 50 
+ 40 
+ 30 
+ 20 
+ 10 
- 10 
-20 
-30 
-40 
-50 
-60 
-70 
-80 
Chart I. Prevalence of trypanosomes in Mus rattus and Mus decumanus, Bombay, 
1905, 1906. 
- =Mus rattus. 
. —Mus decumanus. 
represented these figures in Chart II in the same manner as has been 
done in Chart I, and it will be seen that the prevalence curve based on 
Lingard’s figures approximates very nearly to our own curves 1 . 
1 For convenience of comparison the months in Chart II are arranged in an order 
which is not entirely consecutive, but this does not appear to us to invalidate a general 
comparison between the two charts. 
Lingard apparently examined all rats available without reference to age. 
