title: A working hypothesis concerning the fine structure of the rod outer segment in the frog retina.
mesh_terms: D000818:Animals; D001001:Anura; D008854:Microscopy, Electron; D010786:Photoreceptor Cells / Q000033:anatomy & histology*; D012168:Retinal Pigments / Q000032:analysis
chemical_list: D012168:Retinal Pigments