During the summer of 1948 an investigation of the phycomycetous flora of the Douglas Lake Region of Northern Michigan, Cheboygan County, was initiated. While the work centered for the most part around the Biological Station of the University of Michigan situated on Douglas Lake, collections were also made in the Cross Village area in Emmet County on Lake Michigan, and from the numerous beach pools on Mackinac Island, Mackinac County. The investigation was continued in roughly the same area during the summer of 1950. The writer is responsible for the final identification of all fungi listed except certain of the saprolegniaceous forms which were kindly contributed by Terry W. Johnson, Jr.