The Collaborative International Dictionary of English v.0.48:

Pandean pipes \Pan*de"an pipes\, n. pl.,
   A primitive wind instrument, consisting of a series of short
   hollow reeds or pipes, graduated in length by the musical
   scale, and fastened together side by side; a syrinx; a mouth
   organ; -- said to have been invented by the god Pan. Called
   also pipes of Pan, Pan's pipes and Panpipes.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Syrinx \Syr"inx\, n.; pl. Syringes. [NL., from Gr. ? a pipe.]
   1. (Mus.) A wind instrument made of reeds tied together; --
      called also pandean pipes.
      [1913 Webster]

   2. (Anat.) The lower larynx in birds.
      [1913 Webster]

   Note: In birds there are two laringes, an upper or true, but
         voiceless, larynx in the usual position behind the
         tongue, and a lower one, at or near the junction of the
         trachea and bronchi, which is the true organ of the
         voice.
         [1913 Webster]