New and Unidentified Species of Synchytrium. V

SUMMARY

Three species of Synchytrium, which were formerly identified as S. fulgens and S. aureum, are diagnosed and described as new species. Synchytrium linariae and S. echinulatum are long-cycled and develop prosori, sori, sporangia and resting spores in succession. They are, accordingly, placed temporarily in the subgenus Microsynchytrium, pending discovery of the manner by which their resting spores germinate. Synchytrium davisii, which is short-cycled and develops only resting spores, is included in the subgenus Pycnochytrium. In addition nine unidentified species are described on new hosts from Colorado, Montana, Oregon and Washington, U.S.A., and France.