306 BACTERIA IN THE SPUTA 



multiplication in saliva, the countless swarms of analogical forms, 

 quiescent or reproductive, in the whole wide surface of the nasal 

 cavities, and perhaps of its appendages ; considering also the 

 extraordinary fertility of this parasite, and its multiplication not 

 only through the fission of cocci and bacteria, but through fructi- 

 fication and budding within the filaments, we may form an approx- 

 imate idea of the mass of germs or scattered elements which are 

 invading the digestive, aerial, and lachrymal passages. 



According to my calculations, not less than from two to three 

 hundred trillions of germs or separated elements are generally 

 present in the mouth and nose, and liable to disseminate the 

 species, at every minute, into the other parts. 



In fact, comparing the single sporules of the ears with the 

 dumb-bell bacteria of types «, I), c, d (Fig. 2), we should have to 

 place nearly eight sporules in two rows upon the surface of a single 

 bacterium in order to cover it. The bacterium is twice as thick as 

 the sporule ; consequently, the volume of one bacterium will be, 

 at least, equivalent to that of sixteen minute sporules. Now, in 

 our first Memoir, we have demonstrated that about 25 milliards 

 of bacteria of types a, b, c, d, go to form a centigramme in 

 weight ; then, for every centigramme of sporules, we shall 

 have to multiply the 25 milliards by 16, which will give 400 

 milliards of sporules for each centigramme. Calculating now 

 the considerable number of the dropped sporules, that of 

 the gemmules of reserve in the filaments, that of even the 

 most minute granules which constitute the bed of the branch- 

 ing threads and of the clods of Leptothrix ; calculating the very 

 small lineal germs grafted on the young productions by points^ 

 we can safely maintain that their extreme minuteness compensates 

 for the larger volume of bacteria enclosed in the older filaments, 

 that of spindle-like, the comma, and the serpentine bacilli, as well 

 as of spirilli and cocci disseminated in every part. Thus, holding 

 the volume of the sporule as the unity of measure, taking the 

 whole patina of the thirty-two teeth as equivalent, at least, 

 to a gramme, we shall have the number of the elements and 

 germs living on the dental patina equal to the product of 400 

 milliards (in about a centigramme), x 100, viz., 40 trillions. 

 To these figures is to be added the huge mass of germs and 



