The Collaborative International Dictionary of English v.0.48:

Saxicolous \Sax*ic"o*lous\, a. [See Saxicoline.] (Bot.)
   Growing on rocks.
   [1913 Webster]

WordNet (r) 3.0 (2006):

saxicolous
    adj 1: growing on or living among rocks [syn: saxicolous,
           saxatile, saxicoline]