Collins, Holden & Setchell, Phycoth. Bor.-Amer.
Collins, F.S.; Holden, I.; Setchell, W.A. [1-2300]

Yale University Herbarium
Catalog #: YU.094944
Henri Hus s.n.
Phormidium fragile Gomont
United States, Missouri, Saint Louis; in a copper tank