14 
extent, probably as much as 30 to 40 per cent. of all organisms 
present belonged to this variety, yet the organism is quite rare 
in the dry weather. For some entirely unknown reason 
these organisms which up to this time were exceedingly rare 
suddenly became very common. 
It is true, as demonstrated by the Table II (c), that human 
feeces are apparently subject to much less violent variation 
than cowdung, but it may be fairly safely stated that whenever 
a prevalence of any organism is observed in one it is also to 
be found in increased quantities in the other. 
We consider, speaking broadly, that Table II (c) bears 
out this. The falling-off in the number of coli communis in 
both cattle and human feces in 1908 has been already pointed 
out. This fact has been noticed in all subsequent hot seasons. 
The mere figures do not represent how great is the change. 
We have sought through dozens of samples of human feces 
and cowdung, in order to find one specimen rich in coli com- 
munis without success. In July and August 1908, Ig09 and 
1g10 during monsoon weather about one sample in four was 
-crowded with these organisms. 
Note the presence in large numbers of cloacee in cowdung 
in series Nos. 1 and 2, the smaller numbers in human feces, 
followed by their absence from series Nos. 3, 4, 8, 9, 10 and 11 
in human feces, their absence from cowdung in series Nos. 5, 
6, g and ro and the reduced numbers in Nos. 2, 3, 4, 7 and 8. 
Observe the steady increase in the numbers of coscoroba 
in both human feces and cowdung. 
The presence of organism No. 67 in fair quantity in series 
1 in both human feces and cowdung, and its disappearance 
from nearly all other series, is also significant. 
We do not wish to push this too far because it cannot be 
said to be an absolute rule ; but from experience in the labor- 
atory we are prepared to state that— 
(1) there appear to be seasons when certain organisms 
are commoner than at other times; different varieties of 
organisms are few in the hot weather, plentiful in the rains ; 
(2) when an organism is found commonly in cowdung, it 
is nearly always present, though not necessarily in the same 
quantity in human feces ; and 
