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Research Bulletin No. 1 
curved 3-septate conidium and only rarely the non-septate form, 
altho this can be changed by putting the fungus under hard con 
ditions. Fusarium solani shows a fair differentiation of its basal 
and apical spore cells. 
Fusarium tuberivorum shows all the spore forms that have 
been noted in species of Fusarium. Normally, however, a pre- 
ponderating number of 1 -septate and only a few 3-septate ones 
occur. The spores show no decided differentiation in their basal 
and apical cells. Under proper conditions, only non-septate 
spores appear, and these show no differentiation of their ends. 
Under other conditions the number of 3-septate spores can be 
greatly increased and the most typical end differentiation 
realized. 
Fusarium orthoceras shows the simple sort of conidiophore 
and only at times a simple tri-sterigmate one. Fusarium solani 
ordinarily shows a compound conidiophore and rarely the simple 
types. Fusarium tuberivorum usually shows the orthoceras type 
but can be made to develop the most complex sort of a conidio- 
phore built on the tri-sterigmate plan. 
Fusarium orthoceras shows typical intercalary and terminal 
chlamydospores ; some species of Fusarium have neither. Ordi- 
narily Fusarium tuberivorum has none but under extreme condi- 
tions it can be forced to develop both the terminal and the 
intercalary kind. As far as size is concerned the spores of 
Fusarium tuberivorum stand with the smallest of the species of 
Fusarium, being a little wider than those of Fusarium orthoceras 
and not so long, and a little longer than those of Fusarium solani 
and not so wide. 
FUSARIUM TUBERIVORUM SP. N. WILCOX AND LINK. 
The following diagnosis is based upon the characters displayed 
by this fungus when grown on potato plugs in diffuse light at 
22° to 27° C. 
Conidia not in layers (Pionnotes on glucose agar, sporodochia 
occasionally on old dry tubers of Solanum tuberosum). Normal 
mature conidium fusiform to slightly clavate, slightly bent, no 
differentiation of terminal cells; 1-septate, generally 3-5x7-20 mu. 
Few 0-, 2-, 3-septate spores, 2.4-3.3x7-13 mu; limits 4-7 septate, 
5.2x40 mu. 
Conidial color pale pink, Repertoire des Couleurs des Chrys- 
anthemists, P- 135, No. 3, turning to ochre when very old. 
Conidiophores simple, sterigma-like, short, occasionally branch- 
ing in a tri-sterigmate manner. 
Subaerial mycelium white, appearing flesh pink, Repertoire, 
p. 13fi. No. 1, when mixed with conidia. Chlamydospores appear 
