The Collaborative International Dictionary of English v.0.48:

Notopodium \No`to*po"di*um\, n.; pl. L. Notopodia, E.
   Notopodiums. [NL., fr. Gr. nw^ton the back + poy`s, podo`s,
   the foot.] (Zool.)
   The dorsal lobe or branch of a parapodium. See Parapodium.
   [1913 Webster]