GENERAL SYSTEMATIC BACTERIOLOGY 63 



1. Rods forming free cysts, in which they remain unmodified. Cysts 



various, sessile or borne on a more or less highly developed cystophore. 



Chondromyces B. and C. 



2. Rods forming large rounded cysts, one or more free without gelatinous 



matrix raised above the substratum... .Polyangium K. 



3. Rods slender, swarming together after a vegetative period to form 



definite more or less encysted, sessile or stalked masses of coccus-like 

 spores Myxococcus Thaxter 



Particular attention was called to the group of spirochetes by the 

 discovery by Schaudinn (1905) of the causal organism of syphilis. It 

 was first named Spirochaeta, later Vuillemin (1905) proposed Spiro- 

 nema. This name was invalid under the rules of priority, so Schau- 

 dinn (1905) proposed Treponema and Stiles and Pfender (1905) a 

 little later the name Microspironema. Two other new generic names 

 were proposed during this year, Erythrobacillus by Fortineau for a 

 red pyogenic rod, and Semidostridium by Maassen for a spore-producing, 

 gelatin-forming bacterium from sugar vats. 



Blanchard (1906) discussed the relationships of the spiral organ- 

 isms, and concluded that they should be placed in two groups, the plant 

 forms in the Spirobaderia and the forms more closely related to the 

 protozoa imder Trypanosomidae. The following key gives the principal 

 points of differences recognized. 



Blanchard's Classification of Spiral Organisms (1906) 



I. Spirobacteria, Cohn 1875, Bacteria more or less curved, sometimes the curve 

 forming only an arc of a circle, at other times forming spirals of several or 

 many turns. Organisms little or not at all flexible, multiplying by trans- 

 verse division. Endospores formed in a number of species. 



A. Non-motile Spirosoma Migula 1900 



B. Motile: 



1. Cells rigid, forming a segment of a circle or united into spirals; 



1, 2 or 3 polar flagella Vibrio Ehrenberg 1838 



2. Cells definitely spiral: 



a. With endogenous spores. Flagella not polar. 



Spirobacillus Metchnikoff 1889 



b. With or without endogenous spores. Flagella polar. 



Spirillum Ehrenberg 1838 

 II. Trypanosomidae Doflein 1901. Flagellum continuous in the form of a spiral 

 with turns more or less numerous. Organisms flexible, form more or less 

 fixed, multiplying by longitudinal division. No endogenous spores 

 Gram — , not cultivable by ordinary means in laboratory: 

 A. Form constant, greatly elongate: 



1, Undulating membrane present, cells flattened. 



Spirochaeta 1838 Ehrenberg 



