Amplexicaulineamplexicauline:
(adj) (of leaf bases) clasping the stem
leaves have
bases clasping the stem, while with perfoliateperfoliate:
(adj) (of leaves) with base or margins completely surrounding stem
leaves, the stem appears
to pass through the leaf. A sheathing leaf has a broad base or petiolepetiole:
(n) the stalk of a leaf
that surrounds the stem (sometimes completely) or may overlap other leaf
bases or petioles. Note that leaves may be sheathing even if a stem is
compact and not visible (not illustrated below).