hypopterygei, hypopteryg1aceæ

pl. [Mod. Lat. hypopteryg ( ium ): Lat. masc. pl. adj. suff. -ei, or fem. -aceӕ.] Bot .: A tribe or family of pleurocarpous mo es, having the leaves in two opposite straight rows, united on the upper side of the stem with a third medium row of smaller stipuliform leaves, on the under side having a resemblance to the intermediate leaves in Selaginella; the cells of the leaves are parenchymatous, and equal in all parts. All the genera are exotic. ( Grifith & Henfrey .)