IO4 f 
TABLE X (a)—Contd. 
Percentage number of typical B. colt, which did not ferment 




Saccharose. 
| Raw Thames | Raw Lee Raw New| New River 
1910-11. | Thames filtered Lee filtered River filtered 
Month. | water. water. | water. water. water. water. 
| 247 4,861 | 247 410 247 1,401 
_ samples samples | samples. samples. | samples. | samples. 
Coals. | I 2 | 3 4 5 
IQIO 
April FO°7 3734 72°9 Nil. 63°9 I out of I 
May 50°0 58°6° | 50°0 o out of 2 65°5 3 ws wae 
June 50°0 3455 4 62°5 3° ara 63°0 30°0 
July saat 2°2 38°6 44°0 t | aa 38°3 25°0 
August .. | Br A 48°7 58°1 7 aE a 40°4 46°60 
September | 555 a5°7 40°0 41°6 48°1 33°4 
October .. | 78°60 spies Ti 2 1 out of 3 65°9 3 out of 8 
November 69°2 69°9 74°7 2 S 69°5 TA 
December 80°'0 Ta. of 3: agate pee 76°0 55'1 
IQII. 
January .. | Fo. | 74°9 67°6 7 out of 8 62°5 48°3 
February.. 07. | 81°6 86°0 ee Fe 2 67°7 5 out of 8 
March 79°0 | 62°5 757, 2 aa 58°3 one” 
Average 68°1 hee 66°7 50°9 60°3 56°3 
(7oO | (1,277 | (737 (55 (522 (274 
specimens) specimens) specimens) specimens) specimens)) specimens) 
Some of the figures in columns 4 and 6 are too few in number to be dealt with by 
this percentage method. 


There is no evidence that coli communis multiplies when 
passed into water in nature; on the contrary there is a large 
amount of evidence that it dies out with considerable 
rapidity, particularly when it is subjected to the action of 
the sun rays. Certain figures collected from Dr. Houston's 
report also tend to confirm the statement that coli communis 
is a delicate organism. Two tables taken from his report 
demonstrate the fact that his ‘‘typical bacillus coli’’ is 
rarer In summer than it is in winter. Of course, Houston’s 
“typical bacillus coli’’ includes some §& or Io organisms, 
but work on sewage and feces at home show that amongst 
these 8 or 10, coli communis of Escherich is probably the 
commonest organism; consequently, although his figures 
cannot be quoted as absolute proof, it is highly probable 

