For that matter, the first time I heard "cephalopod" with a hard "c" I wondered about that, but IIRC it's from the Greek "kephalos" (cognate with Latin "capitus"), so it probably OUGHT to be pronounced with "kephalopod" but I've never heard that from an American. A similar thing with the "Keratopsians" isn't it? Anyone up for "Rhinokeros"? (Gk "keras" : Lt "cornus").