GENERAL CHARACTERS OF SPIROCH^TES. 43 



these organisms are a stage in the development of some 

 other form. 



The best-known example of such constant associa- 

 tion is that of the spirochaste met with in Vincent's an- 

 gina with the fusiform bacilli which are often regarded 

 as the cause of this condition. The idea that the 

 two forms may be stages in the life-history of one and 

 the same organism is attractive and is supported by 

 the experiments of Ruth Tunnicliffe who found that 

 in cultures of B. fusiformis spirochsetes made their 



FIG. 53. Spirochaeta vincenti (a) with fusiform bacilli (6) and 

 (?) filament of cladothrix (c). 



appearance. This observation has not, however, been 

 confirmed. Schmiedlechner found bacilli which di- 

 vided longitudinally along with Vincent's spirochaetes. 

 Organisms resembling B. fusiformis were found by 

 Mayer along with Sp. duttoni and by Krzystalowicz 

 and Siedlecki with Sp. pallida; and Leishman, Harvey 

 and Bousfield, and Launois and Loederich noted the 

 coexistence of Sp. pallida with fusiform bacilli in syphi- 

 litic lesions. Wellmann found Sp. pertenuis along 

 with fusiform bacilli and with Sp. refringens. 



Other bacterial forms are also found associated with 

 spirochaetes, as by Button, Todd and Tobey in onychia, 

 by Schereschewsky in syphilis (B. pyocyaneus), by 



