New YorK AGRICULTURAL EXPERIMENT STATION. 195 
wider differences, under varying conditions, in the thermal 
destruction point of certain other enzyms. This must at least 
niake one cautious in accepting conclusions drawn from such 
evidence. | | 
Kissling (1889) studied the pathogenic action of Botrytis 
cinerea and found that it formed a poison which kills the 
protoplasm of the invaded tissues, and which he thought en- 
zymic and the same as the ferment secured by de Bary from 
Peziza.- Kissling did not, however, differentiate between the 
two changes which occur, viz., the death of the protoplasm and 
the dissociation of the cells. 
Kean (1890) showed that the decay of sweet potatoes and 
other vegetables as a result of the invasion of Rhizopus nigri- 
cans (Mucor stolonifer) is due to an enzyin which softens the 
tissues, but he does not give the details of the changes as 
secured under the microscope. He found a similar softening 
by the juice expressed from potato leaves infested with Phy- 
tophthora infestans, also from a Botrytis growing on stone 
crop (Sedum). 
Miyoshi (1895) observed the penetration of the walls of 
different plants by Botrytis and Penicillium and inferred the 
presence of an enzym, but did not isolate it. 
Behrens (1898) published the results of his extensive studies 
upon the pathogenic action of Botrytis vulgaris (B. cinerea)'® 
upon fruits and clearly distinguished between the toxic and 
cytolytic action. -He showed that there is a toxin developed 
which is not destroyed by boiling, thus confirming de Bary’s 
observations, and in addition an enzym or enzyms which acted 
like de Bary’s in causing dissociation of the cells. He found 
enzymic action from Penicillium glaucum and P. luteum, but 
only upon the middle lamella. In order to determine the 
relation to cellulose and calcium pectate respectively he grew 
these fungi for forty-eight days on culture fluids containing 
Swedish filter paper. He found that Botrytis reduced the total 
solids whereas these increased with the other two. He con- 
cludes that Botrytis is capable of dissolving cellulose, probably 
teSmith, R. E., shows these names to be synonyms. 
