[Vor. 1, 1914) 
80 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
the salivary coccus form could not be found in the open air 
devoid of the immediate presence of human beings. 
It thus appears that the presence of the salivary coccus form 
in air indicates the presence of man; furthermore, it indicates 
the pollution of air by particles of mucus from the mouth. 
Flügge ' and his school have shown that pathogenic organisms 
may be transmitted into the air, and other workers ? have shown 
that the tubercle organism is capable of being carried by even 
such feeble air currents as ordinarily exist in dwellings. 
The tubercle organism, as well as the characteristic salivary 
organism, is present in the saliva of tubercular patients. If, 
therefore, this salivary organism can be isolated from the air 
by means of the filter used in the above experiments, does it 
not follow that the tubercle organism could be isolated in a 
similar way? Since our manner of breathing is comparable 
to the operation of the apparatus used, it follows that the tuber- 
cle organism may be inhaled by man. 
It thus appears that the presence in the air of the most char- 
acteristic salivary organism is an index of the possible access 
of pathogenic organisms to the atmosphere. 
In conclusion, the writer wishes to express his thanks to Dr. 
Geo. T. Moore, for valuable suggestions and numerous courte- 
sies extended during the progress of the work; to Dr. J. R. 
Schramm, for suggestions, and aid in the preparation of the 
manuscript; and to Mr. Wilson F. Monfort, Chemist of the 
City of St. Louis Water Department, for advice given and op- 
portunities provided for the collection and examination of the 
samples. 
EXPLANATION OF PLATE 
PLATE 2 
Air-sampling apparatus showing support, sand filter, pinch cock, exhaust and 
suction tubes, and pressure bulb. 
1 Gordon, M. H. loc. cit. 
: Kolle and Wassermann, Handbuch der pathogenen Mikroorganismen 1: 169. 
