[VoL. š 
16 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
which oidial formation occurs in cultures of certain Pasidio- 
mycetes that I subsequently suggested the presence of such 
an oidial stage of this fungus (Duggar, '09). Owing to the 
transfer of the cotton disease work to Dr. С. L. Shear at this 
time the material was laid away, and not again examined un- 
til a recent reinvestigation of all material in my hands which 
might be considered related to Rhizoctonia. Then it was as- 
certained that the best packet of material collected in 1902 
had not been studied—that from the area found between the 
rows of cotton. The reéxamination of this collection resulted 
Fig. 1. Phymatotrichum omnivorum: types of conidiophores and conidial 
production. 
in finding in some abundance the hyphae which bear the 
spores. It was furthermore ascertained that the spores were 
produced at first on the characteristic larger hyphae and on 
small branches of those hyphae which make up the strands 
of the fungus in the soil. Typically, the attached conidia 
were found in heads about short swollen, but not necessarily 
spherical, branches of the short-celled or strand hyphae. 
These branches were simple or forked, the forking being at 
irregular intervals, and occasionally branching was contin- 
ued from a swollen cell (fig. 1). The spores adhered some- 
