452 
Journal of Agricultural Research 
Vol. XXVI, No. 10 
resemble F. incarnatum (Rob.) Sacc., as per Wollen weber’s figures in 
the supplement to his “ Fusaria aut. delineataj but include none with 
more than 5 septa. 
Habitat.—In red discolored wood of box elder, Acer negundo Linn., 
Madison, Wisconsin, United States of America. 
Sherbakoff states that, “The general appearance of the fungus on 
hard oat agar in a test tube is shown in Plate 1. Free spore production 
on mycelium is very sparse and the conidia are of the type shown in 
Figure 1, B. Sporodochia in the media used are rarely produced, in fact 
only in one culture (a Petri-dish culture on hard potato agar plus 3 per 
cent dextrose-maltose) sporodochia appeared, and then in a compara¬ 
tively large number, mostly one-fourth to 1 mm. in diameter, free, i. e., 
without a pseudoparenchymic base, with conidia of light-salmon color. 
When the culture was 8 days old the septation and size of conidia from 
the sporodochia were as follow’s: o-septate very few; 1-septate, 1 per 
cent; 2-septate, not observed; 3-septate, 30 per cent, 3.5 x 31.5 (3.1-3.9 
x 29-37)' fi; 4-septate, 32 per cent, 3.85 x 35.7 (3*7—4- 2 x 3 r -5-39) AG' 
and 5-septate, 37 per cent, 4.1 x 37.5 (38-4.2 x 35-40) ju. Another exam¬ 
ination of conidia from the same sporodochia, when the culture was 30 
days old, gave the following results: o-septate, 2 per cent; i-septate, 7 
per cent; 2-septate, 2 per cent; 3-septate, 8 per cent; 4-septate, 9 per 
cent; and 5-septate, 72 per cent; the latter measuring 4.4 x 39.2 (3.9-6.1 
x 34-42) fx. The conidia are shown in Figure 1, A.” 
MORPHOLOGY 
The conidia (fig. 2, G.) are typical sickle-shaped spores with the 
characteristics as given by Sherbakoff. Macroconidia, microconidia, 
and chlamydospores are formed, both in artificial cultures and upon the 
exposed surfaces of the host, although up to the present time macro¬ 
conidia have been found less frequently upon the host than the other 
forms. 
A six-day-old culture on malt agar, No. 91, when examined, showed 
large septate hyph&e, constricted at the septa, with contents varying in 
color from yellowish to bright red and containing many large vacuoles 
(fig. 2, K.). Anastomosing of hyphae appears to be common in this 
species and reference to this character is made by Eidam. 
The fungus develops readily from pieces of infected wood placed in 
moist chambers, and in most cases no great difficulty was experienced in 
securing pure cultures on various agars by using fragments of the dis¬ 
colored wood as inocula. On several occasions, however, the fungus 
has failed to develop from such fragments and this may be explained by 
the fact that microscopical examination of some of the stained wood 
discloses no hyphae within the tissues. 
In eight-day-old Petri-dish cultures using malt agar the aerial growth 
covered the entire surface. From the under side the central area of the 
growth in Petri-dishes is of a pomegranate purple color and the outer, 
more recent, growth area an olive lake color. 10 The growth is more 
rapid and the discoloration of the substratum is more intense on prune 
and oatmeal agars than on malt agar. 
Both terminal and intercalary chlamydospores are formed in cultures 
(fig. 2, D.). These spores may be single but more often are in chains 
10 Ridgway, Robert, color standards and color nomenclature. 43 P-. S 3 col, pi. Washington, 
D. C., 19M. 
