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decision (1891). M. Ward took the Bakteroiden to be the spores - 
of a true hyphal fungus. Ericksson also took them for a spore 
or bacterioid buddings from true hyphe. 
The “Infectionsftiden” seem to be another cause of much contro. 
versy. Frank formerly likened them to the Sc/inzia (Plasmodio- 
phora) Alni of Woronin and called them Schinzia leguminosarum. 
As will be seen from his conclusions of 1890 and 1891 he defi- 
nitely states that they are not a fungus, but a production of the 
normal plant cells used for the purpose of infection. M. Ward 
took the Infektionsfiden for the real fungus of which the Bakte- 
roiden were the spores. Prazmowski at first took them for 
plasmodia filled with small rod-like bodies. As soon as the 
plasmodium enters the root cells it surrounds the entire cell 
contents so that plasmodium and cell contents can not be distin- 
guished. Later he changes his opinion and takes the Infektions- 
faden for hyphe-like tubes filled with bacteria. That is, the 
hyphz-like tubes, if not identical with Frank’s Infektionsfaden, 
at least have a similar function. Schroeter seems to be satisfied 
that the Infektionsfaden are true plasmodia made up of swarm 
spores of his Phytomyxa leguminosarum. 
At present I shall not enter into any further discussions of 
existing controversies, but shall proceed with my own observations 
and resultant conclusions. In my observations I studied the 
Rhizobia as 1 found them in the various Leguminose. Frank 
and Beyerinck, so far as I can learn, made their principal obset- 
vations on culture Rhizobia. These cultures are apt to lead t 
erroneous results for three reasons: First, because but little is at 
present known of their behavior outside of their host; second, 
because the same tubercle may contain a variety of RAizobia and 
other bacteria, especially tubercles that have begun to break 
down—these would be liable to influence the culture formations; 
third, because of the well known fact that culture fluids greatly 
modify the appearance of bacteria, Frank seems to give "° 
plausible reason why there should be but one species of Rhizobium. 
Frank and Beyerinck both admit that this one species occurs in 
a variety of forms, Y-shaped, oblong, curved, etc. In the exam- 
ination of normal culture soil solution I found not only a variety 
of Riuzobia, but also a host of other bacteria, bacilli and micfo” 
