The Manning Canyon Shale on the eastern slope of Lake Mountain in Utah County, Utah contains an Early Pennsylvanian flora within its upper shales. Many of these fossils appear to be new species. A microscopic study of the tissue remains can be of value in the further classification of these fossils. Selected fossils were macerated in hydrofluoric acid, and the residues were examined microscopically for tissue remains. Objects identified as fossil tissue remains were found in twenty five of the forty-eight specimens examined. Fibers, fiber tracheids, tracheids, and spores were isolated from fossils identified as Calamites. The spores were possibly recent fungus spores from the laboratory. Most of the fossils identified as Cordaites had little or no remaining organic material, but one fiber and a peel showing the outlines of cells which were presumed to be epidermal cells were found. A fiber and a fiber tracheid were isolated from a Lepidostrobus. A spore was found in the maceration residue of a fossil identified as Lepidodendron but was too decomposed to be classified as to the type of spore. Many of the fossils collected from the Manning Canyon Shale appear to be portions of stems, roots, or rachises of undetermined affinities. These were lumped together for this study under the classification of "stems." Xylem elements, cuticles, sclereids, and an