59 



From this we learn that by using for infection of the 

 sea water a considerably smaller number of B. coli communis, 

 and therefore the number initially ingested by the oysters 

 being relatively small, it made no appreciable difference 

 in the manner and time in which the oysters became clear 

 of the B. coli communis, as compared with the oysters of 

 the preceding experiment in which the initial number in 

 the sea water was ten times greater. 



Table VIII gives a summary of the results of Experi- 

 ment VIII, and for comparison we repeat Table VII as 

 Table IX, giving the analysis both of the wet oysters of 

 Experiment VIII and of the oysters of previous Experi- 

 ment VII. 



TABLE VIII. 



SEA WATER INFECTED WITH NORMAL FAECAL MATTER. 

 SEA WATER. 



Immediately after infection. 22,000 B. coli communis per 1 c.c. 



After 48 hours .... 440 



After 1 day's change . 40 



After 2 days' change . . per T ^ c.c. 



OYSTERS. 



Oyster 3 48 hours in infected sea water, contained 650 B. coli 



communis per oyster. 



5, 4 after 1 day's change, contained 84 B. coli com. per oyster. 

 5 2 days' 600 



6 3 484 



" ' " 



" j> 48 ,, ,, 



" ' )> ,, ,, per i part 



of oyster. 



10 8 18 per oyster. 



11 8 per | part 



of oyster. 











5) 52 ,, ,, 



