Leathesia difformis Areschoug
Annotated by Robert F. Scagel.

Washington: San Juan: Brown Island, near Friday Harbor.
48.533333° N, 123° W,
Coordinate Source: Specimen Label.
On rocks, and epiphytic on other algae in the upper intertidal zone.; rock, epiphytic. Other Number: 1; Thallus up to 6 (12) cm in diameter, yellowish brown in colour; mature thallus of irregular outline with a much convoluted surface and hollow in center. Interior of thallus with colourless dichotomously and radiately branched filaments with progressively smaller cells toward the surface. Outermost portion of thallus with club-shaped or rounded cells in assimilating filaments, and occasional fascicles of colourless multicellular hairs. Https://oregonflora.org/collections/individual/index.php?occid=4680224.

Robert F. Scagel 21, 1955-7-1
OSC, Catalog: OSC-A-009406, Accession Number: 10001