i:)4 



Decompo)<it!on of Cellulose 



cultivation under unfavourable conditions is frequently followed by 

 intense granulation of the thread form. This is evident, for example, 

 in cultures containing an excess of nitrogen or, in fact, of soluble organic 

 substances generally — nutrient beef agar, 1-0 per cent, peptone, 0-5 per 

 cent, asparagin, and also in dilute solutions of phenol, etc. The most 

 pronounced changes of this type were observed in cultures which, in 

 error, had been subjected to a temperature of 36°-37° for some days. 

 The culture that actually underwent this exposure was characterised 

 by hnv stain receptivity, the majority of the cells showing phases such 

 as are represented in Plate II, figs. 2 and 3. On transference of this 



Fig. 1. 



culture to a lower temperature (25°) and especially on inoculation to 

 fresh medium, almost all the filamentous forms exhibited strong granu- 

 lation, and this characteristic persisted for at least two generations 

 after the culture had ceased to be under unfavourable conditions 

 (Plate III, fig. 6). Well-marked granulation is of interest morpho- 

 logically, in that it imparts to the cell an appearance somewhat similar 

 to that found by Leishman^ to be possessed by spirochaetes giving rise 

 to the formation of "coccoid granules." There is no evidence however 

 that these granules of Spirochaeta cytophaga have any special significance. 

 A further divergence from the normal course appears to be the 

 formation of a pre-sporoid stage possessing either double granules or a 

 band of nuclear substance (Plate II, figs. 3 and 4). The general for- 



1 Leishman, W. B., Tram. Soc. Trap. Med. Hyg. 1010, 3, 97. 



