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

Brown University - Algae
Catalog #: ABRU00003984
I. Holden s.n. 08 May 1892
Spirogyra porticalis (O.F.Müller) Dumortier
United States, Connecticut, Brookfield, CT

Yale University Herbarium
Catalog #: YU.094289
Isaac Holden s.n. 08 May 1892
Spirogyra porticalis (O.F.Müller) Dumortier
United States, Connecticut, Brookfield; Brookfield, CT

University of Michigan
Catalog #: 736715
Isaac Holden #s.n. 08 May 1892
Spirogyra porticalis f. minor (O.F.Müller) Dumortier
United States, Connecticut, Fairfield, Brookfield

University of Michigan
Catalog #: 736720
Isaac Holden #s.n. 08 May 1892
Spirogyra porticalis f. minor (O.F.Müller) Dumortier
United States, Connecticut, Fairfield, Brookfield

Michigan State University Algae
Catalog #: MSC0184798
Isaac Holden #s.n. 08 May 1892
Spirogyra porticalis (O.F.Müller) Dumortier
United States, Connecticut, Fairfield, Brookfield

Miami University - Algae
Catalog #: 000188259
Isaac Holden #s.n. 08 May 1892
Spirogyra porticalis (O.F.Müller) Dumortier
United States, Connecticut, Fairfield, Brookfield