4o6 MANUAL OF BACTERIOLOGY. 



non-pathogenic, by the use of collodion sacs placed in the peri- 

 toneal cavity of apes. MetchniKoff and Roux found the same 

 organism in the monkeys which they had successfully inocu- 

 lated with syphilis. 



The evidence is accumulating rapidly in favor of this 

 organism as the cause of syphilis.* It is 4- to 14 p- long, 

 \ /J- thick and has 6 to 14 turns. It is actively motile. Stained 

 with great difhculty. The following stain was recommended 

 originally, and more recently a variety of stains have also been 

 employed by different observers: 



(i) Three parts Giemsa's eosin solution (2.5 c.c. i per cent, eosin solution 

 in 500 c.c. water). 



(2) Three parts asur I solution (i gram asur in looo c.c. water). 



(3) Three parts asur II solution (0.8 gram in 1000 water). 



Mix and stain dried cover-glass preparations from 16 to 24 hours; wash, 

 dry and mount in balsam. 



Spirochaeta Refringens. — Found less frequently than S. 

 pallida in the same locations as the latter. Is larger and 

 stains more easily than S. pallida. 



*Spirobacteria in the Lesions of Syphihs. Journal of the American Medical 

 Association. Vol. XLIV., No. 22. p. 1790. 1905. 



Schultz. Journ. Med. Res. XV. 1906. pp. 363-381. 



