234 The Celenj-Rot Bacillns 



the film by passing through a flame it is stained with Heidenhain's 

 haematoxylin. The differentiation with the mordant after staining is 

 continued until the organic compounds of the bouillon are decolourized 

 leaving only the bacteria stained (Fig. 6). 



It would seem that the abnormal forms here described have not 

 come under the observation of previous workers on soft-rot organisms. 

 Harrison says (12) of Bacillus oleraceae, " Involution forms are commonly 

 found. Thus the bacteria may be ovoid, or long and bent, occasionally 

 club-shaped individuals are seen"; but the extreme forms apparently 

 he did not observe. Jones writes (16) of B. carotovorus, " Pleomorphis- 

 mus ist selten beobachtet worden. In verschiedenen, zwei Monate 

 alten Kulturen (Rohren mit gedampften Mohren) hatten viele Stabchen 

 ovale, lichtbrechende Stellen in Innern, die stark an Sporen erinnerten, . . . 

 sie fiir Vakuolen geh alten." 



Erwin F. Smith in his monograph (36) figures^ long filaments of 

 Bacterium campestre from an old culture (about 5 weeks old) on 23 % 

 grape sugar agar ; he also finds^ that old cultures of Bacterimn hyacintJii 

 "on media rich in sugar... of ten show many long slender chains and also 

 filaments 50 to 150 /x long in which no septa are visible." 



Miss Doidge shows (7) that Bacillus mangiferae in beef broth con- 

 taining 7 to 8-75 % NaCl "grows out into long threads which are very 

 variable in length and thickness" ; some of these threads were swollen 

 irregularly and apparently resemble those forms described above as 

 occurring in the synthetic medium with 6 % alcohol. 



IV. Cultural Observations. 



Growth in Media containing Sugar. The bacillus was cultivated 

 in Durham's tubes and in fermentation tubes in media containing 

 peptone (Witte's) and one of the sugars dextrose, lactose, and saccharose 

 prepared with litmus solution. Several batches of the media have been 

 prepared and inoculated with the following general result. The media 

 invariably developed acidity as indicated by a reddening of the con- 

 tained litmus. 18 hours after inoculation (incubated at 28° — 29° C.) 

 the dextrose solution assumed a distinct red tint which approximated 

 to that finally attained by all three; in the saccharose solution the 

 reddening was evident but rather less intense, while with lactose there 

 was but slight change from the original neutral tint. The reddening 



1 Loc. cil.. Vol. I, Fig. 19. - Loc. cil , Vol. ii, pp. 344-5 and P'ig. 141. 



