Indusium

Indusium hidden beneath the sporangia, consisting mostly of a few hair-like divisions.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium formed by the reflexed margin of the pinnules.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium ample, segments broad, frond without hairs.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium fixed beneath the sori, thin and often evanescent, either small and open, or early bursting at the top into irregular pieces or lobes.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium formed of the reflexed margins of the fertile segments which are more or less membranous.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium conspicuous, at length splitting into several spreading, jagged lobes.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium cup-shaped, fixed beneath the sorus, supported by the tooth of a leaf; sporangia borne in an elevated, globular receptacle open at the top.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium minute, concealed beneath the sorus, divided into a few beaded hairs.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium fixed under the sporangia, appearing like a tiny green cup filled with spore cases.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton

Indusium straight or rarely curved, fixed lengthwise on the upper side of a fertile veinlet, opening toward the midrib.

The Fern Lover's Companion A Guide for the Northeastern States and Canada George Henry Tilton