Fig. 44-11. Membranous labyrinth. Note the ampullae of the semicircular ducts. The black lines and areas in the ampullae, utricle, saccule, and cochlear duct represent the neuro-epithelium: the ampullary crests, maculae, and spiral organ, respectively. Two cross sections are included. C.D., cochlear duct; S.C.C, semicircular canal; S.C.D., semicircular duct; S.T., scala tympani; S.V., scala vestibuli. Click for high resolution image.