Source : Webster's Revised Unabridged Dictionary (1913)

Erythrogen \E*ryth"ro*gen\, n. [Gr. 'eryqro`s red + -gen.]
   (Chem.)
   (a) Carbon disulphide; -- so called from certain red
       compounds which it produces in combination with other
       substances.
   (b) A substance reddened by acids, which is supposed to be
       contained in flowers.
   (c) A crystalline substance obtained from diseased bile,
       which becomes blood-red when acted on by nitric acid or
       ammonia.