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£72 BOTANICAL GAZETTE [SEPTEMBER 
it as a new species. He told the writer in 1913 that he felt con- 
vinced that we had described one and the same thing. Comparative 
studies made by the writer during the past year verify this point of 
view, and since the Nebraska publication by Witcox, LINK, and 
Poot (40) did not appear in print until 1913, the name F. tricho- 
thecioides should be adopted. 
WOLLENWEBER (41, 42) published a further paper in which he 
categorized the Fusarium spp. very sharply, dividing the genus’ 
into sections on the basis of physiological (that is, pathogenicity) 
and morphological (that is, conidia and chlamydospores) characters. 
F. oxysporum was again established and taken as the representative 
of the section ELEGANS, which comprises vascular parasites; and 
_F. trichothecioides was put into the section Discotor, which com- 
prises parenchyma destroyers. He distinguished sharply between 
these and also between the vascular ring-discoloring Fusarium 
species of section ELEGANS and the tuber-rotting Fusarium species 
of sections DiscoLor, GIBBOSUM, MARTIELLA, etc. 
Referring to the papers by SmirH and SwINGLE (35), MANNS 
(24), and others, particularly to that by Manns, he writes: ‘‘ They 
do not separate fusarioses causing tuber rot from those causing both 
the wilt diseases of the plant and ring discoloration of the tuber, 
so that the reader might conclude that both wilt disease and tuber 
rot are caused by the same organism.”’ Referring to his own experi- 
ments, he writes: “It also brings out the striking fact that the 
fungus, a typical xylem inhabitant, does not entirely destroy the 
tuber without the help of tuber rot Fusarium or bacteria,” and 
“the fact that F. oxysporum causes the wilt of growing potato plants 
and only uses the xylem of the stem end of tubers for over-wintering, 
without producing a rot of the parenchyma, leads to interesting 
comparisons with the following 4 species which are able to destroy 
the tuber entirely from artificial wounds, namely, F. coeruleum 
(Lib.), F. trichothecioides Wr.,’’ etc., and finally ‘the fact that the 
latter (F'. oxysporum) cannot produce a tuber rot gives a biological 
contrast to the wound parasites of the tuber, and the fact that they 
cause the wilt disease of the growing plant presents a contrast to 
the saprophytes.”’ 
