The Collaborative International Dictionary of English v.0.48:

Jew's-ear \Jew's"-ear`\, Jew's-ears \Jew's"-ears`\, n. (Bot.)
   A widely distributed species of edible fungus (Auricularia
   auricula-judae, formerly Hirneola Auricula-Jud[ae], or
   Hirneola Auricula), bearing some resemblance to the human
   ear and growing on decaying wood.

   Syn: ear fungus, .
        [1913 Webster + WordNet 1.5]