资料来源 : pyDict

外珠孔

资料来源 : Webster's Revised Unabridged Dictionary (1913)

Exostome \Ex"o*stome\, n. [Exo- + Gr. ? mouth :cf. F. exostome.]
   (Bot.)
   The small aperture or foremen in the outer coat of the ovule
   of a plant.