542 
PROFESSOR H. MARSHALL WARD ON THE 
they are undoubtedly the same as those found by Eriksson. Frank also found the 
hyphse here and there in cells containing the minute corpuscles (these corpuscles are 
the “vibrios” or “bacteria” of Woronin and Eriksson) : these corpuscles are cells, 
and not mere granules ; their form varies ; some are rod-like or curved, or shaped like 
a finger-biscuit, others Y-shajied, and so on. They seem to increase by budding, but 
this is assumed only. They have no proper movement, as Woronin supposed. 
The hyphse are thicker than the above corpuscles, and grow through from wall to 
wall across the lurnina of the cells. They may end in the cavity, and in any case are 
rarely traced through more than two cells or so. Frank and Schenk both regarded 
certain short branches in the cells as haustoria. 
Frank then goes into the question as to the continuity of the hyphse and the 
bacteria-like corpuscles. Are there two parasites present in the swellings ? Without 
actually deciding the point, Frank has little doubt that the corpuscles are budded 
oil' from branches of the hyphse. 
No results were obtained on trying to cultivate the corpuscles beyond the putting 
out of a fine hypha from either end in one or two unsatisfactory cases. 
Frank regarded the parasite as allied to that described by Woronin in the Alder, 
and named it Schinzici leguminosarum. 
Kny # replied to Frank’s Paper that he regarded the corpuscles as the spores of a 
plasmodium ; the strand-like extensions of the latter show no membrane, and abut 
on the wall with curious funnel-like widenings—this is clearly the case in Frank’s 
figures. Schwendener is also quoted as viewing the strands as membraneless 
plasmodial strands. Kny also states that De Vries and others have seen the 
tubercles on the roots of water-cultures. 
This appears to be a satisfactory account of the position of our knowledge of these 
curious structures up to date : it resolves itself into the following. While it is 
certain that some organism or other exists in the tubercles, no observer has cleared 
up the question as to whether there is one constant Fungus present, or whether it is a 
plasmodium which causes the hypertrophy, or whether two forms coexist in the 
cells : it is also uncertain how the parasite (if there is only one) enters the tissues— 
whether from the soil into the root, as seems so probable from Eriksson’s and 
Frank’s researches, or whether it is already present in the seed. The latter is a 
more improbable suggestion, and we may dismiss the idea that no parasite exists at 
all, in spite of the doubts implied in Sorauer’s statement on p. 744 of his book, 
and of the very general belief to the contrary which exists among agriculturists 
especially. In any case, however, no one had as yet succeeded in infecting the roots, 
and producing the tubercles artificially. I have done this, and may now proceed to 
describe my own observations and experiments. 
I first commenced the microscopic examination of the tubercles in 1883, but, 
although the investigation was renewed each year since, the really important additional 
* ‘ Sitzungsber. cl. Rotan. Vereins d. Prov. Brandenburg - ,’ 1879 (Jnne 27), p. 115. 
