A new site for plant fossils of Lower Carboniferous (Mississippian) age has recently come to our attention. The deposits are intercalated in gypsum from strata in subsurface mines near Grand Rapids, Michigan. Marine Ctenocanth spines and teeth are accompanied by lycopod fragments from the upper surface and layers of the gypsum. Samples for palynological analysis were collected from abandoned galleries. Included in the collections from the mine roof and layers fallen from the roof were fragments of arborescent lycopod stems and considerable flotsam derived from proximal marine margins. Fibrous material, scraps of periderm, and shredded woody tissue were also collected. Spore analysis indicates probable Namurian age. Absence or very low percentages of such key spore genera as Tripartites, Grandispora, Schulzospora, Densosporites, and Lycospora presently preclude a more definitive age determination.

Key words: gypsum, Mississippian, plant fossils, western Michigan