This pair of Secamone alpini leaves seen from below show their pale, lower surfaces. The leaf margins are strongly rolled under, matching the midrib that is raised here, not on the upper surface. Parallel lateral veins spread to the margins, curving up as they get near.
Rusty hairs are sometimes seen on the lower surfaces, not really in evidence here. This photo was taken in the Walter Sisulu National Botanical Garden near the river where this plant was growing naturally, not part of the planted Garden (Pooley, 1998).