Anonymous, Calif. Fungi
Herbarium of the University of California. [1- ? 1425]

Cornell University, Plant Pathology Herbarium
Catalog #: CaliforniaF.00338
s.n.
Sphaerotheca humili (DC) Burr.
United States, California

USDA United States National Fungus Collections
Catalog #: BPI 948045
s.n.
Sphaerotheca humuli (DC.) Burrill
United States, California

Michigan State University Herbarium
Catalog #: MSC0212978
J. P. Tracy s.n. 28 September 1930
Sphaerotheca humuli (DC.) Burrill
United States, California, Humboldt, Big Lagoon

Field Museum of Natural History
Catalog #: C0286332F
d7b486fe-a5cf-436d-900b-bb61f8eb1460
J. P. Tracy #s.n. 28 September 1930
Sphaerotheca humuli (DC.) Burrill (DC.) Burrill
U.S.A., California, Humboldt, Big Lagoon

Washington State University, Charles Gardner Shaw Mycological Herbarium
Catalog #: WSP35264
J.P. Tracy s.n. 28 September 1930
Sphaerotheca humuli (DC.) Burrill
United States, California, Humboldt, Big Lagoon

Iowa State University, Ada Hayden Herbarium
Catalog #: ISC-F-0118861
J.P. Tracy #s.n. 28 September 1930
Sphaerotheca aphanis (Wallr.) U. Braun
USA, California, Humboldt, Big Lagoon;