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]

The Collaborative International Dictionary of English v.0.48:

Auricula \Au*ric"u*la\, n.; pl. L. Auricul[ae], E.
   Auriculas. [L. auricula. See Auricle.]
   1. (Bot.) (a) A species of Primula, or primrose, called
      also, from the shape of its leaves, bear's-ear.
      (b)
      (b) A species of Hirneola (Hirneola auricula), a
          membranaceous fungus, called also auricula Jud[ae],
          or Jew's-ear. --P. Cyc.
          [1913 Webster]

   2. (Zool.)
      (a) A genus of air-breathing mollusks mostly found near
          the sea, where the water is brackish.
      (b) One of the five arched processes of the shell around
          the jaws of a sea urchin.
          [1913 Webster]