New YorkK AGRICULTURAL EXPERIMENT STATION. 193 
Behrens (1902) studied further the organisms concerned 
with the different methods of flax retting. He found that in 
all cases alike the essential thing is the solution of the middle 
lamellae of the parenchyma cells. He concluded that in the 
latter process a specific anaerobic bacillus is the agent, while 
‘in other processes fungi (Mucors) take the active part. 
Haumann (1902) studied the flora of retting flax and con- 
cluded that there are numerous species of bacteria and fungi 
active in the process. He found several of these species capable 
of liquefying calcium pectate. 
Doubtless further search would reveal other records of the 
solution of the middle lamella without evidence of the solution 
of the cellulose layers. It may safely be inferred, in our judg- 
ment, that the action in most of these cases was like that in 
the soft-rot organisms studied in our laboratory. These cita- 
tions will at least suffice to emphasize the point that such ac- 
tion on middle lamellae apart from action on cellulose is a 
common occurrence in bacterial fermentation. It must not be 
concluded, however, that cytolytic action by bacteria is con- 
fined to the middle lamella and like parts of the wall. While 
this is the action concerning which we have the most detailed 
evidence, proof is not lacking that there are bacteria capable 
of causing the.full solution of parenchyma walls, and even of 
the more resistant cellulose of fibre. 
EK. F. Smith (1908) has shown this in his painstaking work 
upon the black rot of the cabbage caused by Pseudomonas 
campestris, 
No other equally convincing evidence has come to our atten- 
tion as to like action by bacteria parasitic upon plants. We 
have no doubt, however, that such cases will be found not 
infrequently as bacterial plant diseases are more fully investi- 
gated. 
Omelianski (1895) began in 1894 a study of the solution of 
normal or typical cellulose as represented by Swedish filter 
paper. The final summation (1902) of his painstaking work 
shows that at least two species of bacteria are capable of caus- 
ing the complete solution of this most resistant cellulose. He 
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