FOSSIL VEGETABLE MATTER OF OIL SHALE OF GREEN RIVER FORMATION (GENERAL VIEWS). From thin sections prepared by C. A. Davis. A, Magnified 410 diameters; B, magnified 215 diameters. FOSSIL VEGETABLE MATTER OF OIL SHALE OF GREEN RIVER FORMATION (DETAILED VIEWS). From thin sections prepared by C. A. Davis. 4, Pollen, magnified 245 diameters; B, left, yellow-green alga, magnified 740 diameters; right, (?), magnified 120 diameters; C, left, spores, magnified 200 diameters; right, fern annulus, magnified 685 diameters. |