1914] , 
NOLTE—SALIVARY ORGANISMS AND AIR POLLUTION 77 
fallen during the preceding 18 hours. A total of 10,800 cc. of 
air was drawn through the apparatus at the rate of 830 cc. per 
minute. Samples of the sand solution were plated as shown in 
table rx. It is to be noted that in those plates containing 1 cc. 
of the solution no colonies developed, whereas in those contain- 
ing 5 cc., 1 bacterial colony appeared in each. Attention is called 
to the consistent results in this experiment to emphasize the 
fact that the inconsistencies in experiment 12 are due to local 
contamination. No salivary cocci were found. 
Experiment 14.—The air sample for this experiment was taken 
on a bright, clear day, with a rather strong wind blowing and a 
temperature of 55°F. А total of 10,800 cc. of air was drawn 
through the sand filter at the rate of 1,080 сс. per minute. 
Samples of the sand solution were plated as shown in table rx. 
Of the 3 coccus forms, 2 gave negative reactions on all three 
differential media, whereas 1 was positive on saccharose and 
negative on lactose and milk. The latter will be recognized as 
one of the unidentified coccus forms. No salivary cocci were 
isolated. 
Summarizing the open air experiments, it is to be noted that, 
barring the locally contaminated plate 1 in experiment 12, the 
characteristic salivary coccus form was not isolated; further- 
more, that the total number of organisms in the open air is 
comparatively low. 
SUMMARY AND CONCLUSIONS 
Examining the entire series of experiments it appears that 
in the majority of cases where ventilation was obviously inad- 
equate, the characterisitic salivary coccus form was isolated. 
On the other hand, the form could in no case be found where 
ample artifieial or natural ventilation existed. 
It has been shown that the most characteristic salivary 
organism can be differentiated and identified; also, that this 
characteristic organism can be isolated from the air. 
In the experiment carried on in one of the street cars in which 
there were many passengers, the characteristie salivary coccus 
form was found to be present in such quantities as to indicate 
that the air in this car was “unsafe.” It was later shown that 
