The Collaborative International Dictionary of English v.0.48:

Barometz \Bar"o*metz\, n. [Cf. Russ. baranets' clubmoss.] (Bot.)
   The woolly-skinned rhizoma or rootstock of a fern (Dicksonia
   barometz), which, when specially prepared and inverted,
   somewhat resembles a lamb; -- called also Scythian lamb.
   [1913 Webster]