Algae | Bryophytes | Pteridophytes | Gymnosperms | Angiosperms   »   Rosidae Prunus endocarp This is an anatomically preserved endocarp, or stone from the genus Prunus from the middle Eocene Princeton chert locality of British Columbia. Prunus is the genus for the drupe- or stone-bearing fruits of the Rosaceae, subfamily Prunoideae, including cherries, plums, apricots, and peaches. In the photograph the thick golden-colored layer is the endocarp, or stone, which represents the innermost fruit wall. This contains a single large seed. Fossil wood of this group is also known rom the Princeton chert. Citations Cevallos-Ferris, SRS, and RA Stockey. 1991. Fruits and seeds from the Princeton chert (middle Eocene) of British Columbia:  Rosaceae (Prunoideae). Bot. Gaz. 152: 369-379. Arizona State University | Department of Plant Biology