Beggiatoa. 



39 



Fig. i'i.—BeggiaUa. pellmida, X 400 (after Cohn). 



55- B. mirabilis, Cohn {I.e., p. 8i). 



Threads very thick, motile, bent and curled in various 

 ways, with rounded 

 ends, distinctly 

 jointed, as much as 

 16 /i thick; articu- 

 lations about half 

 as long as broad, 

 filled with nume- 

 rous, pretty large 

 granules. Threads 

 twisted round and 

 entangled with one 

 another, forming a 

 snow-white web of 

 gelatinous threads. 



(Fig- 33-) 



With the preceding 



Fig. 33. — Beggiatoa mirahilis, X about 320 (after 

 Cohn). 



Doubtful Species. 



56. B. tigrina, Rabenhorst ("Flor. Eur. Alg.," ii. 



P- 95); 

 Oscillaria tigrina, Romer. 

 Threads pretty thick, oscillating, distinctly jointed, with 

 blunt and slightly bent, sometimes abruptly attenuated 

 and crooked ends, translucent, 3'S-4"S /* thick; forming thin 

 white layers. (Fig. 29^.) 



In marshes and on wood under water. 



