204 
Journal of Agricultural Research 
Vol. V, No. s 
A. SECTION MARTIEEEA 
[Species in this section are F. solani (Mart.) Sacc., F. martii App. and Wollenw., F. eumartii, n. sp., F. 
coeruleum (L,ib.) Sacc., and F. radicicola Wollenw.) 
1. Fusarium solani (Mart.) Sacc. (i, p. 77). 
Conidia normally triseptate (PI. XIV, fig. 3) up to 100 per cent, occurring in 
pionnotes and sporodochia, 1 averaging 30 to 40 by 5 to 6/u. Limits of normal tri¬ 
septate conidia: 25 to 45 by 4.5 to 6.5/4. Seldom 2 and 4, exceptionally 1 and 5 
septate (limits: 1-septate, 15 by 4/4 minimum; 5-septate, 59 by 6.5/4 maximum; greatest 
width, 7/4; highest septation, 7.) Conidial mass brownish white, becoming brown in 
age; often greenish as a result of infiltration with greenish blue pigment from the 
plectenchymatic mycelium. Chlamydospores terminal, intercalary, and conidial; 
unicellular, round or pear-shaped, 8.5 by 8 m; 2-celled with constriction at cross wall, 
12 by 7.75/4; smooth, rarely in chains or clumps. 
Habitat . —On decaying tubers and roots of plants and in the soil. Isolated from 
species of Solanum, Citrullus, Cucumis, Cucurbita, Lycopersicon, Pinus, Hibiscus, 
Avena, Zea, Triticum, Panax, Citrus, Pelargonium. Collected by various investi¬ 
gators and identified by Wollenweber and Carpenter. 
F. solani (sensu strict) is regarded as a saprophyte, but apparently 
it acts as a weak wound parasite under exceptionally favorable con¬ 
ditions. 
2. Fusarium coeruleum (Lib.) Sacc. (1, p. 90). 
Conidia normally triseptate (PI. XIV, fig. 5), averaging 30 to 40 by 4.5 to 5.5/1 
(limits of normal triseptate conidia: 23 to 47 by 4.25 to 6/4); seldom 4 and 5 septate 
(limits: triseptate, 23 by 4.25/4 minimum; 7-septate, 58 by 5.75/4 maximum). Coni¬ 
dial mass brownish white and yellow ocher to reddish ocher. Plectenchymatic stroma 
chiefly violet to indigo blue and bluish black; by infiltration with the latter color 
the conidial masses may become bluish green, as in other species of the section Mar- 
tiella. F. coeruleum is the only species of the section having reddish ocher conidial 
masses. Chlamydospores as in other species of the section. 
Habitat.—On tubers of Solanum tuberosum. Established as a cause of tuber rot 
in this country and in Europe by Wollenweber (20, p. 44). Determined by Dr. 
Wollenweber and the writer in material from the following localities: Ottawa, Canada; 
Houlton, Me.; Rhinebeck, N. Y.; Fredericksburg, Md.; Norfolk, Vd.; Parkersburg, 
W. Va.; Donnybrook, N. Dak.; Idaho Falls, Idaho; Potlatch, Wash.; and several 
places in Oregon. 
3. Fusarium eumartii, n. sp. 
F . eumartii isolated from the Pennsylvania dry-rot agrees with Appel and Wollen¬ 
weber’s (1, p. 78-84) diagnosis of F. martii except in certain details of the conidia. 
The latter in the new species are higher septate and have a somewhat larger average 
size (Pl. XIV, fig. 4). Normally 4 to 6 septate, averaging 54 to 75 by 5.5 to 6.6/4 
(limits: 50 to 80 by 5 to 7.2/4). Largest conidia 85 by 7.2/4 (7 and 8 septate). Per¬ 
centages of variously septate conidia, average sizes and limits as found in a 10-day- 
old pionnotes on Melilotus alba and in a 15-day-old pionnotes on cotton are given in 
Table VII. 
1 For definition of these terms see Wollenweber, H. W. (20, p. 24)- 
