from The Century Dictionary and Cyclopedia
- In botany, not having an indusium: applied to ferns.
Sorry, no etymologies found.
 See Moore, 'Nature-Printed Ferns,' 8vo, for numerous illustrations both of depauperate and exindusiate ferns.
The contraction and imperfect development of the fronds of some varieties of ferns, hence called depauperated, may receive passing notice, as also the cases in which the sori or clusters of spore cases are denuded of their usual covering, owing to the abortion or imperfect development of the indusium, as in what are termed exindusiate varieties. [