Rootstock, root-like trunks or portions of stems on or under ground, [42].

Roridus, dewy.

Rosaceous, arranged like the petals of a rose.

Rostellate, bearing a small beak (Rostellum).

Rostrate, bearing a beak (Rostrum) or a prolonged appendage.

Rosulate, in a rosette or cluster of spreading leaves.

Rotate, wheel-shaped, [89].

Rotund, rounded or roundish in outline.

Ruber, Latin for red in general. Rubescent, Rubicund, reddish or blushing.

Rudimentary, imperfectly developed, or in an early state of development.