Identification of Phytophthora Species : by L.H. Leonian.

ORGANISMS STUDIED An attempt was made to secure all the described species of Phyto- plithora.Three important species, namely, P. infestans, P. thalictri, and P. phaseoli, have been left out of the following list of organisms because we already have sufficient data on these species for an accurate and speedy identification.Certain other species, probably of no taxonomic value, could not be obtained in pure culture from any source ; nor do we have full descriptions of them.