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OUTLINES OF BACTERIOLOGY 



1. Streptothrix. Simple undivided threads. Division takes place in 

 one direction of space only (Fig. 14). 



2. Cladothrix. In this genus the threads are composed of small rods 

 enclosed in a membranous tube (Fig. 15). The appearance presented 



FIG. 14. Streptothrix. (a) Under 

 low power of microscope ; (6) small 

 portion very highly magnified. (After 

 Migula.) 



FIG. 15. Cladothrix. (After Zopf.) 



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FIG. 16. Cladothrix dichotoma, showing false 

 branching. (After Zopf.) 



by a colony of Cladothrix dichotoma is shown in Fig. 16. There is no 

 true branching, as the apparent branches are formed by the slipping 

 aside of single cells, which subsequently form threads, but remain 

 attached to the parent plant. Here we see a good example of a 

 community of individuals. Each thread is made up of a number of 

 short rods (similar to those of the genus bacillus) and the membrane 



