The Collaborative International Dictionary of English v.0.48:

Pyxie \Pyx"ie\ (p[i^]ks"[i^]), n. (Bot.)
   Same as Pixy.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pyxie
    n 1: creeping evergreen shrub having narrow overlapping leaves
         and early white star-shaped flowers; of the pine barrens of
         New Jersey and the Carolinas [syn: pyxie, pixie,
         pixy, Pyxidanthera barbulata]