CHAPTER XXV 



PATHOGENIC TRICHOMYCETES. MOLDS. YEASTS 



THE trichobacteria appear to hold a position intermediate 

 between the lower forms of bacteria and the molds. Structurally 

 and functionally they are more complex than the former and 

 much simpler than the latter. Certain authorities consider they 

 should all be grouped together under the name of streptothrix 

 and placed with the molds ; other authorities hold a different view. 



Hence their classification is 

 still undecided. 



The characteristics of the 

 group are (1) an irregular, 

 thread-like growth of interde- 

 pendent segments, one end of 

 which may be free while the 

 other remains attached to an 

 object, and (2) the develop- 

 ment of a special portion of 

 the organism for the purpose 

 of reproduction and a tendency 



FIG. 38. Trichomycetes. i i t i /TJ- 



to branching true or false (r ig. 



38). In false branching two terminal cells are developed from a 

 parent cell, one of which is pushed aside but remains partly 

 attached to the main stem. As the two cells continue to develop 

 the appearance of branching is produced. In certain forms, when 

 reproduction is about to take place, small, rounded cells known as 

 conidia or spores appear either at the free end of the organism or 

 at intervals along the filament, from which new individuals de- 

 velop. Such spores are more closely related to those of the molds 



266 



