Source : Webster's Revised Unabridged Dictionary (1913)

Nervation \Ner*va"tion\, n.
   The arrangement of nerves and veins, especially those of
   leaves; neuration.

         The outlines of the fronds of ferns, and their
         nervation, are frail characters if employed alone for
         the determination of existing genera.    --J. D.
                                                  Hooker.