580 CG. CLIFFORD DOBELN. 
representing a primitive or degenerate method of conjugation. 
If this interpretation is correct, then a fact of the utmost 
importance has been discovered—a fact of deep significance 
not merely as regards the affinities of the Bacteria, but also 
in relation to the general problem of sex. 
For some years no confirmation of these observations was 
forthcoming; until, owing to the fortunate discovery of a 
new organism very like B. biitschlii, I was able—in 1907— 
to corroborate, in its essential points, the work of Schaudinn. 
Of the accuracy of Schaudinn’s observations, I have myself 
no doubt whatever. But I cannot now regard his deductions 
from them as correct. 
For various reasons, it seemed to me that the process which 
Schaudinn (1902) and others—including myself (1908)—were 
driven to regard as a form of conjugation, was, perhaps, 
capable of being interpreted in some other way. After much 
idle guessing, I concluded that the only method of throwing 
light upon the problem was to make a very careful study of 
sporulation in other Bacteria. Although so much has been 
written on this subject, it has been treated as a cytologic 
problem by but few investigators. And this is scarcely sur- 
prising, as the work has usually been done for medical pur- 
poses and upon organisms of very small size. One of the 
ereatest difficulties which I encountered was that of obtaining 
species of Bacteria of sufficiently large size for exact observa- 
tion. After many failures, I have now succeeded in following 
out the method of spore-formation in two large parasitic 
Bacteria which throw—as I believe—a considerable amount 
of light upon the ‘ 
“sexual” phenomena. It is my purpose 
in the following pages to describe these organisms and 
those stages in their life-histories which concern the problem 
under consideration. In a later part of the paper (p. 587) 
I shall point out the new point of view to which my 
researches have led me, and its consequences. 
The descriptions which follow are based on a study of the 
organisms in their natural habitat. I have not isolated them 
