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

Brown University - Algae
Catalog #: ABRU00004231
M. A. Howe s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island, Bahamas

Field Museum of Natural History
Catalog #: C0528354F
M. A. Howe #s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island, [precise locality unknown]

Yale University Herbarium
Catalog #: YU.094538
Marshall A. Howe s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island, Bahamas

Drexel University, Academy of Natural Sciences - Algae
Catalog #: PH00212063
977fb475-6bec-435b-8d5b-8b664a84fec2
Marshall A. Howe #s.n 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island, Bahamas

University Herbarium, University of California, Berkeley
Catalog #: UC1827924
Marshall A. Howe #s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island, Cat Island

University of Michigan
Catalog #: 732007
Marshall A. Howe #s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island

University of Michigan
Catalog #: 732014
Marshall A. Howe #s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island

Michigan State University Algae
Catalog #: MSC0184702
Marshall A. Howe #s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island

Miami University - Algae
Catalog #: 000188566
Marshall A. Howe #s.n. 23 November 1907
Siphonocladus rigidus M.A.Howe
Bahamas, Cat Island