Cephalopoda (Nautilids, octopods, cuttlefishes, squids, and relatives) Phylum Mollusca Number of families About 45 Thumbnail description Mollusks bearing a radula (toothed tongue) and well-developed heads; mouth characterized by a dorsoventral pair of horny jaws known as beaks and encircled by the bases of 8-ca. 60 grasping appendages; single pair of lateral, image-forming eyes; well-developed brain […]