6 
Research Bulletin No. p 
The credit of first demonstrating experimentally the relation of 
Fusariitm spp. to certain plant wilts belongs to Smith (34), who 
found a Fusariitm responsible for watermelon wilt. Smith and 
Swingle (35) reported a potato wilt and tuber rot which they 
considered due to a Fusarium which they called F. oxysporum. 
They considered this organism identical with F. solani of Pizzigoni 
and W^EiiMER, and used the oldest name available, F. oxysporum 
( SciiLEcriTEXDAHL, 1824) ; however, they reported no experimental 
inoculations. Petiivbridge and Bowers (28) reported a dry rot 
due to F. solani. and Longman (22) also reported a dry rot due 
to a Fusariuin. 
Many ])athol()gists and mycologists entertained considerable 
doubt as to the parasitic nature of Fusarium spp., while others were 
quite convinced of their parasitic nature. Sorauer (36) was quite 
positive in his decision, while Massee (25) wavered. Lindau (18) 
remained skeptical and referred to the F. oxysporum of Smith 
and Swingle as a "Mischart.'' Dtggar (10) was quite positive 
in his decision. Much of this difference of opinion undoubtedly 
was due to the confusion that prevailed as to the status of F. solani, 
F. oxysporum, and the genus in general, since no basis for extended 
morphological study of the genus had been established, and even the 
genus itself had not been sharply defined. Massee (25) considered 
F. solani to be the conidial f(^rm of Nectria solani; while Reinke 
and Bertiioldt (30) considered it the conidial form of Hypomyces 
solani. Tot:nsburv (23) tried to arbitrate the matter by suggest- 
ing that F. solani and F. oxysporum are one and the conidial stage 
of Nectria solani. Appel and Wollenweber (5) published a 
monograi)h in which they defined the genus and brought some 
order into the chaos of species. Among other radical changes they 
drop])ed F. oxysporum and established F. orthoceras in its place. 
Maxxs (24) demonstrated by experimental inoculation tliat a 
Fusarium, which he designated (following Smith and Swingle) as 
F. oxysporum, could produce tuber rot and wilt. He made no 
morphological studies, however, and undoubtedly had not had 
access to Appel and Wollenweber's monograph. 
Jamteson and Wollenweber (16) published an account of a 
dry rot of tu])ers induced by a Fusarium which they described as a 
