J.B. Ellis, B.M. Everhart, and E. Bartholomew [1501-5100, plus extras]

Cornell University Plant Pathology Herbarium
Catalog #: F.Columbiani-4927
C. A. Ludwig s.n.
Gymnosporangium R. Hedw. ex DC.

University of Nebraska State Museum, C.E. Bessey Herbarium - Fungi
Catalog #: NEB00054429
C. A. Ludwig s.n. 29 April 1916
Gymnosporangium clavariaeforme (Wulfen) DC.
United States, Michigan, Washtenaw, Ann Arbor;

Michigan State University Herbarium non-lichenized fungi
Catalog #: MSC0251487
C. A. Ludwig s.n. 29 April 1916
Gymnosporangium clavariaeforme (Wulfen) DC.
United States, Michigan, Ann Arbor;

Field Museum of Natural History
Catalog #: C0275747F
719a457f-f50c-4932-a9cd-bac4b68298d7
C. A. Ludwig #4927 29 April 1916
Gymnosporangium clavariiforme (Wulfen) DC. (Wulfen) DC.
U.S.A., Michigan, Washtenaw, Ann Arbor; Ann Arbor

Miami University, Willard Sherman Turrell Herbarium
Catalog #: 000270266
C. A. Ludwig #4927 29 April 1916
Gymnosporangium clavariaeforme (Wulfen) DC.
United States, Michigan, Washtenaw

University of Michigan Herbarium
Catalog #: 278431
C. A. Ludwig #s. n. 29 April 1916
Gymnosporangium clavariiforme Dietel
USA, Michigan, Washtenaw, Ann Arbor.

University of California Berkeley, University Herbarium
Catalog #: UC1458359
C. A. Ludwig #s.n. 29 April 1916
Gymnosporangium clavariiforme Dietel
USA, Michigan, Washtenaw, Ann Arbor

Chrysler Herbarium - Mycological Collection
Catalog #: CHRB-F-0008360
C.A. Ludwig #. 29 April 1916
Gymnosporangium clavariaeforme . .
United States, Michigan, Ann Arbor;

University of Wisconsin-Madison Herbarium
Catalog #: WIS-F-0018347
C.A. Ludwig #s.n. 29 April 1916
Gymnosporangium clavariiforme Dietel
United States, Michigan, Ann Arbor;

Brown University Herbarium
Catalog #: CBRU00003191
CA Ludwig s.n. 29 April 1916
Gymnosporangium clavariaeforme (Wulfen) DC.
United States, Michigan, Washtenaw, Ann Arbor;

USDA United States National Fungus Collections
Catalog #: BPI 117401
Ludwig C. A. s.n. 29 April 1916
Gymnosporangium clavariiforme (Wulfen) DC.
United States, Michigan, Ann Arbor

USDA United States National Fungus Collections
Catalog #: BPI 967289
Ludwig C. A. #s.n. 29 April 1916
Gymnosporangium clavariaeforme (Wulfen) DC.
United States, Michigan, Ann Arbor

USDA United States National Fungus Collections
Catalog #: BPI 967389
Ludwig C. A. #s.n. 29 April 1916
Gymnosporangium clavariaeforme (Wulfen) DC.
United States, Michigan, Ann Arbor

Charles Gardner Shaw Mycological Herbarium, Washington State University
Catalog #: WSP2863
Ludwig, C.A. s.n. 29 April 1916
Gymnosporangium clavariaeformae
United States, Michigan, Washtenaw, Ann Arbor