The Collaborative International Dictionary of English v.0.48:

Sarcous \Sar"cous\, a. [Gr. sa`rx, sa`rkos, flesh.] (Anat.)
   Fleshy; -- applied to the minute structural elements, called
   sarcous elements, or sarcous disks, of which striated
   muscular fiber is composed.
   [1913 Webster]