542 R. E. BUCHANAN 



B. Rods forming large rounded cysts, one or more, free within a gelatinous 



matrix raised above the substratum Genus II. Polyangium 



II. Rods transformed to form definite, more or less encysted, sessile or stalked 

 masses of coccus-like spores Genus III. Myxococcus 



Genus I. Chondromyces Berkeley and Curtiss, 1857, p. 313 



Synonyms : 



Stigmatella Berkeley and Curtiss, 1857, p. 70 

 Polycephalumf Kalch and Cke., p. 22 

 Cystohacter Schroeter, 1886, p. 170 

 Myxobotrys Zukal, 1896, p. 346 

 Rods forming free cysts in which they remain unmodified. Cysts 

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

 The type species is Chondromyces crocatus Berkeley and Curtiss. 



Genus II. Polyangium Link, 1795, p. 65 



Synonyms : 



Myxobacter Thaxter, 1892, p. 394 

 Rods forming large rounded cysts, one or more, free within a gelat- 

 inous matrix raised above the substratum. 



The type species is Polyangium vitellinum Link. 



Genus III. Myxococcus Thaxter, 1892, p. 403 



Rods slender, curved, swarming together after a vegetative period 

 to form definite more or less encysted sessile masses of coccus-like 

 spores. 



The type species is Myxococcus rubescens Thaxter 



Order VI. Spirochaetales. Ord. nov. 



Synonyms : 



Spirilloflagellata. Krzysztalowicz and Siedlicki 

 Protozoan-like in many characters. Cells usually relatively slen- 

 der flexuous spirals: multiplication of cells apparently by longitudi- 

 nal division in some types, by transverse division in others, or both. 

 One family is recognized, Spirochaetaceae. 



