APPENDIX I. 



Actinomycetes. 



For the limitation of this group and its genera, see 

 page 127. 



We have conscientiously recorded all that is known to 

 us in the literature regarding forking, branching, etc., in 

 other forms up to this time considered as true bacteria; 

 thus, B. pyocyaneum, B. influenzae, B. tetani, B. radici- 

 cola, Vibrios, — the cladothrix form of B. murisepticum 

 was immediately retracted by Kitt himself, — and we must 

 naturally acknowledge that these observations make it 

 more difficult to perceive in the branching a distinguish- 

 ing peculiarity between actinomycetes and fission-fungi. 

 Innumerable similar difficulties are, however, encountered 

 in the definition of higher plant families — some genera 

 are often placed with equal propriety in one or another 

 family. If at a later time, because of further investiga- 

 tions, the significance of branching should be construed in 

 a manner different from that of to-day, it will still remain 

 true in any case that the actinomycetes of to-day, which 

 we have collected in part upon the basis of branching, will 

 form a perfectly natural family, even if their family diag- 

 nosis should be essentially remodeled. 



i. Corynebacterium. Lehm. and Neum. 



Cultures having throughout the character of cultures of 

 true bacteria; soft, lying flat and loose upon the nutrient 

 media. Stain well with the ordinary bacterial stains, but 

 are not acid proof. Microscopically: Rods, which fre- 

 quently present clubbed swellings at the ends, appear 

 more or less distinctly composed of differently staining 



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