The Collaborative International Dictionary of English v.0.48:

Scyllite \Scyl"lite\, n. (Chem.)
   A white crystalline substance of a sweetish taste, resembling
   inosite and metameric with dextrose. It is extracted from the
   kidney of the dogfish (of the genus Scyllium), the shark,
   and the skate.
   [1913 Webster]