New YorK AGRICULTURAL EXPERIMENT STATION. 1385 
because the parasitism in each case seems directly associated 
with and probably dependent upon the power to produce such 
an enzym. Second, because these soft rot organisms are so 
much alike as to make the question of their specific relationship 
an extremely complex one which must ultimately be settled 
largely by appeal to physiological characters, including their 
ability in parasitism, and it would seem that their enzym pro- 
duction might prove of value in this connection as a differential 
character. Another interesting question of fundamental im- 
portance concerns the relationship of the cytolytic enzyms, or 
cytases, from various sources. We have attempted to deter- 
mine whether the enzym here dealt with is identical with 
those obtained by de Bary (1886)? and Ward (1888) from 
certain fungi, by Brown and Morris (1890) and later investi- 
gators from seeds and by Potter (1899) and others from soft 
rot bacteria. 
In the progress of these investigations a detailed study was 
first made of the enzym as produced by the carrot-rot organ- 
ism, including a comparison of its action when secured in 
various ways apart from the living bacillus, and also as ob- 
served upon the sundry vegetable tissues. Thereafter a com- 
parison was undertaken of the characteristics of the enzyms 
secured from the soft-rot organisms of several other vege- 
tables and finally with wall-dissolving enzyms produced by 
Other classes of bacteria, by fungi and by germinating seeds. 
In the following discussion of the results it will conduce to 
clearness and directness of statements to follow a somewhat 
similar order. It might seem more logical to begin with a 
publication has awaited the conclusion of the associated morphological 
studies, except for a summarized account of the work which appeared in 
the “ Centralblatt fiir Bakteriologie und Parasitenkunde,” 1905, (see Bib- 
liography). Inasmuch as no important contribution to the subject has 
come to our attention meanwhile, it has seemed best to leave the manu- 
script unaltered, and to add no titles to the bibliography later than 1905. 
An important part of the work of the author was done in the botanical 
laboratory of the University of Michigan where he profited from the advice 
of Professor F. C. Newcombe. In the investigations carried on in his own 
laboratory in Vermont, valuable assistance was had from two of his 
students, Messrs. H. D. Bone and L. P. Sprague. He gratefully acknowl- 
edges his indebtedness to these gentlemen. 
*All citations to the bibliography follow the plan of giving in parenthesis 
after the author’s name the year of publication, followed where desired 
with the page numbers specificially referred to. 
