Morphology 549 



varies from 6 to 20; the diameter of the coils varies so greatly 

 that scarcely any two are uniform. Wladimiroff* doubts the 

 existence of a flagellum, but flagella-like appendages are 

 usually to be seen at one or both ends of the organisms. 

 An undulating membrane attached nearly the entire length 

 of the organism, very narrow, and inconspicuous, forms the 

 chief means of locomotion. The organism is actively motile, 

 and darts about in fresh blood with a double movement, con- 

 sisting of rotation about the long axis and serpentine flexions. 

 No structure can be made out by our present methods of 



Fig. 1 88. Spirochaeta duttoni (Novy;. Tick fever, No. 520. Rat 

 blood. X 1500. 



staining and examining the spirochaeta. No spores are 

 found. Multiplication is thought to take place by longitudi- 

 nal division, though some believe the division to be trans- 

 verse. 



The Spirochaeta duttoni is said by Koch,f in his interest- 

 ing studies of "African Relapsing Fever," to resemble the 

 Spirochaeta obermeieri in all particulars. 



The Spirochaeta novyi with which Novy and Knapp t exper- 

 imented, and which they believed to be identical with 



"Kolle and Wassermann's Handbuch der pathogene Mikroorgan- 

 ismen," 1903, in, p. 82. 



f ''Berliner klin. Wochenschrift," Feb. 12, 1906, xxxiv, No. 7, p. 185. 

 J "Jour. Infectious Diseases," 1906, in, p. 291. 



