Dioscorea convolvulacea Cham. & Schltdl.

This herbarium sheet preserves a dried specimen of *Dioscorea convolvulacea*, a twining vine of the yam family, collected in Costa Rica and held by the Natural History Museum, London. The plant's heart-shaped leaves, sinuous stems, and slender flower racemes are pressed flat and pinned to cream mounting paper — standard Victorian herbarium practice. A Flora Costaricensis label records collector Dr. H. Polakowsky and the 1875 gathering date; a later annotation by O. Téllez in 1993 confirms the determination. Herbarium specimens like this one underpinned the systematic botanical illustration tradition — precise, annotated, economical — that fed directly into the diagrammatic visual language later adopted by scientific publishing and, through popular natural-history picture-sheets, into the sequential panel conventions of the modern comic page.