26o 
Journal of Agricultural Research 
Vol. II, No. 4 
or an independent section which could be called “ Lanceolata” because of 
the conidia being lanceolate, especially when seen from the back (PL XIII, 
^ 4 )* 
3. Fusarium culmorum (W. G. Sm.) Sacc. 
Fusisporium culmorum W. G. Sm., 1884,1)is. Field and Gard. Crops, p. 208-210, fig. 92. 
Fusarium Schribauxi Delacr., 1890, in Bui. Soc. Mycol. France, t. 6, fasc. 2, p. 99, pi. 15, fig. 1; Sacc., 
1892, Syll. Fung., v. 10, p. 726. 
Fusarium culmorum (W. J. Sm.) Sacc., 1895, Syll. Fung., v. n, p. 651. 
Fusarium corallinum Mattirolo (non Sacc.), 1897, w Mem. R. Accad. Sci. 1 st. Bologna, s. 5, t. 6, p. 677, 
fig. 16-17. 
Fusarium rubiginosum App. and Wollenw., 1910, in Arb. Biol. Anst. f. Band- u. Forstw., Bd. 8, Heft 1, 
p. 108, pi. 1. 
Diagnosis.—Conidia scattered in sporodochia or in pionnotes in masses ochreous to 
salmon colored, 5-septate, averaging 30 to 45 by 5.5 to 7 fi, seldom 3 to 4-septate, 
rarely with a larger or smaller number of septa. The slight constriction at the apical 
end and the pedicellate base of normal conidia make this fungus a type species of 
the section Discolor. Conidiophores in sporodochia increase to repeatedly verticil- 
late ramifications with sterigmata and side branches as many as four in whorls. The 
mycelium thallus has a yellow acid modification (viz, on rice) turning violet with 
alkaline and a carmine-red basic one (viz, on wheat and potato tuber) turning yellow 
with acid. Chlamydospores intercalated, single, in chains or in clusters, averaging 
7 to 14/z in diameter. 
Habitat.—This species is found in Europe and North America on all parts of partly 
decayed plants. It is a wound parasite on cereals and causes scab and seedling 
blight (foot disease). It has been found on the following hosts: Zea, Avena, Triti- 
cum, Secale, Kordeum, Lupinus, Gossypium, Ipomoea, Beta, Solanum, Cucumis, 
Curcurbita, and others. 
This diagnosis is based on the original strain from an Irish potato 
tuber at Dahlern, near Berlin, described as Fusarium rubiginosum by 
Appel and Wollenweber (1910) and is changed only in the minimum 
average width of conidia and in the distribution of the fungus. 
When the writer studied species of Fusarium on the potato in Ger¬ 
many, he isolated Fusarium culmorum (Pl. XVI, fig. J) from tubers 
affected with dry-rot and described it as Fusarium rubiginosum App. and 
Wollenw. In pure culture it attracted special attention by its carmine 
color on steamed potato tuber. This color always indicated its basic 
modification, while the red turned chrome yellow with acids. An acid- 
yellow modification of the fungus, which turned violet by addition of 
alkali, appeared naturally on steamed rice. This fungus was noted by 
Schaffnit in his important studies of the “Schneeschimmel” of cereals 
(Schaffnit, 1913); he stated a similar range of color shades and illustrated 
this organism very well. 
The conidia of this fungus are characterized by a thick membrane 
and very pronounced cross walls (septa). In maturity they are of 
ochreous color, lighter in small quantities and darker when seen in 
masses, but in young culture, especially in moist pionnotes on potato 
tuber, they may have salmon shades. The presence of chlamydospores 
facilitates the determination when under certain conditions. The conidia 
