97 
were present in 11, and greatly predominated in no less than 8. 
The extraordinary numerical predominance of these organisms 
over all others, may be taken to be very strong evidence in 
favour of the truth of the statement, that these organisms 
are resistant to the action of sunlight. 
Coli communis was isolated once in this quarter, from 
the Marlimund reservoir in Ootacamund. Inspection showed 
that the catchment area was contaminated to a _consider- 
able extent by wood-cutters, in the immediate neighbour- 
hood of the lake, and that light rain was actually falling 
at the time when sample was taken. Coli communis was 
entirely absent from all other samples. 
Second quarter—A very marked difference has come 
over the results of the analyses of samples taken during the 
quarter ending 31st December 1908. First of all, there has 
been a great improvement in the average quality of the 
waters. An approximate average for this quarter is I fecal 
organism in 8c.c. of water. Inno less than 6 out of 13 samples, 
feecal bacilli were only present in 5 c.c. or more. But the 
most important change that is observed between the first 
and the second quarter is best shown by Table IX (b). The 
large falling off in the number of bacillus cloace and in the 
Grunthal-Vesiculosus group is apparent. The great increase 
in organisms, such as lactis erogenes, coscoroba, should be 
observed. Bacillus cloace and Grunthal also persist, but only 
in very much the same proportion as they are found in all 
recently polluted surface waters. It will also be noticed, 
that, as compared with the samples of the previous quarter, 
a mixture of varieties of organisms is the general rule. 
Coli communis were found in one case, namely, in the 
lake at Adoni. The explanation of this cannot be given satis- 
factorily, but it is probably due either to contamination at 
the edge, or to the fact that the supply stream was still 
flowing. 
Third quarter.—The striking feature about the samples, 
taken during this quarter, is the great purity of the waters. 
The approximate average in the samples is 1 fecal organism 
per 40 c.c. of the water. The reason for this is obvious, 
namely, that during this quarter, the large volume of water, 
7 
