18000 



17000 



16000 



15000 



14000 



13000 



12000 



1 1 000 



10000 



9000 



6000 



7000 



6000 



5000 



4000 



5000 



2000 



1000 



1053 



34; 



'595 



8127 



7142 



11480 



6250 



'4873 



3315 



14132 



11542 

 &/ 



Si 



5262 



7340 



930 



17515 



14730 



12285 



6453 



5917 



DIAGRAM V. Means of the foregoing curves, showing average numbers of bacteria 

 for August, October, and December. 



