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

University of Michigan
Catalog #: 736763
N.L. Gardner #s.n. 14 April 1901
Zygnema chalybeospermum Hansgirg
United States, California, Alameda, Boswell, near Berkeley

University of Michigan
Catalog #: 736764
N.L. Gardner #s.n. 14 April 1901
Zygnema chalybeospermum Hansgirg
United States, California, Alameda, Boswell, near Berkeley

Michigan State University Algae
Catalog #: MSC0185306
N.L. Gardner #s.n. 14 April 1901
Zygnema chalybeospermum Hansgirg
United States, California, Alameda, Boswell, near Berkeley

Drexel University, Academy of Natural Sciences - Algae
Catalog #: PH00147929
c3d8a1a8-906f-4b8c-9c09-45fcc51fb216
N.L. Gardner #s.n. 14 April 1901
Zygnema C.Agardh, 1817
United States, California, Alameda, Boswell, near Berkeley