Figure 6 in Phylogeny of families in the Pectinoidea (Mollusca: Bivalvia): importance of the fossil record

Figure 6. Propeamussium sp., Gulf of Mexico, 25°31′N, 95°51′W, 1061–1317 m. Scanning electron micrograph of a fracture through a right valve near the base of the posterior auricle viewed obliquely from the outer side, dorsal margin towards the top. cla, crossed-lamellar aragonite; fc, foliated calcite layer bearing imprint of prismatic layer on its outer surface; pc, prismatic calcite. Scale bar = 50 µm.