438 



p. G. HEINEMANN AND E. E. ECKER 



Leptothrix huccalis, the organism thought to be the cause of 

 caries of teeth. We examined the decayed portion of four 

 teeth after having carefully cleaned the teeth with sterile NaCl 

 solution to avoid the chance of lacto-bacilli being present in 

 the dried saliva on the outside of the teeth. After cleansing 

 the teeth the inside decayed part was scraped out with a sterile 

 knife and placed in acetic acid broth. Otherwise the same 

 technic was employed as with the other material. 



Material for examination was obtained from the following 

 sources : 



From all these cases typical lacto-bacilli were isolated. After 

 four to six transfers in litmus milk the typical appearance of 

 the milk was observed. Stains were prepared from all cultures 

 and the bacilli appeared as large, rather slender or fairly thick 

 organisms with blue granules. They were Gram positive. The 

 colonies were all of the compact type. Sandberg (1904) first 

 called attention to the two kinds of colonies formed by the 

 Boas-Oppler bacillus. One of these has woolly edges, the other 

 is solid. Similar observations have been reported by several 

 authors. 



