Hermann Edward Hasse (12 January 1836 – 29 October 1915) was an American lichenologist.[1][2] He wrote two important texts and numerous articles in his field.[3] Hassea, which is a genus of fungi in the class Dothideomycetes,[4] and Lecidea hassei, a lichen that grows inside solid rock (endolithic lichen), were both named in his honor.[3] He principally did his research in southern California. His correspondents included cryptogamic botanist William Gilson Farlow and lichenologist George Knox Merrill.