AND CONTENTS OF THE MOUTH. 169 



on empty stomachs. Is it to be wondered, then, if their products, 

 and chiefly the Spirillum sputigenum, are so scanty in those persons 

 who regularly clean their teeth ? Miller goes on to say that in 

 unclean mouths they are numberless. 



These microbes are in the shape of small Comma rods, endowed 

 with very quick, screw-like movements. When linked by twos, 

 they form themselves into small snakes, like the letter s. 



Lewis, as we have already said, identified this microbe with the 

 bacillus styled Cholerigemis. However, its presence in the mouth 

 had been detected before, and by a few attributed to fragments of 

 Spirochcete. Clark held it to be the cause of caries, for it pene- 

 trates the dental tubuli as shown in Fig. 17 of Miller. This author 

 excludes every relationship between the Spirillum sputigenutn and 

 the bacillus Cholerigemis^ judging from the culture which for the 

 latter is positive whilst for the Virgula of the mouth it is always 

 negative, However, this is a new confirmation of our views, for, 

 if the Commas in question are real organs or copulative filaments, 

 it is quite natural that, whilst they fecundate the articulations or 

 the spores, they should be incapable of reproduction themselves.* 



In addition to the Spirillum sputigenum, Miller classifies two 

 other types of curved filaments : one short, massive (Fig. 32), 

 and motile, which liquifies gelatine ; the other slender, still, and 

 more curved (Fig. 18). In growing old, it gives rise to a small 



* After having completed our work, we found in the Lancet of June, 1890, 

 an important article by Dowdeswell, on the Comma bacillus of cholera. He 

 touches on the widely-spread hypothesis that those Commas may be only frag- 

 ments of spirilla, and then he describes three cycles in their evolution : — 



A, Commas or fragments of spirilla which may or may not end in sporules ; 



B, Active cellules, with cilia and amoeboid forms ; then round quiescent cel- 

 lules (sporanges) ending in minute sporules ; C, Active filaments ending in 

 sporules of the first generation. The author, however, has not succeeded in 

 reproducing, by any method, the normal Commas, vital and reproductive for 

 themselves. He affirms that cholera bacilli are to be found, normally, in the 

 large intestine of the guinea pig, and that the subcutaneous inoculation of a large 

 number of such bacilli really produces choleriform symptoms in that animal ; 

 but it is not a true cholera infection. Considering the high temperature that 

 accompanies it, it is a true septicaemia. The fact, then, that the author nas 

 found forms of Leptothrix in the Comma bacillus cultures, goes still further to 

 support our views. Dowdeswell, Note on the ' ' Morphology of the Cholera 

 Comma Bacillus," mVnQ Lancet, 1890, Vol. i., page 1419 — 23. 



International Journal of Microscopy and Natural Science. 



Third Series. Vol. V, n 



