Hydrocotyle leucocephala Cham. & Schltdl.

This herbarium sheet preserves a dried specimen of Hydrocotyle leucocephala, a creeping aquatic plant in the family Araliaceae, collected during Auguste de Saint-Hilaire's botanical expedition through Brazil. The pressed stems fan across the mount in looping, vine-like trails, their rounded, scalloped leaves flattened dark by time. Gathered during a formative era of Linnaean systematic botany, such specimens were the raw material from which Chamisso and Schlechtendal formally described the species. Herbarium collections of this period underpinned the explosion of natural-history illustration — the same visual culture that fed satirical broadsheets, where precision draftsmanship trained on anatomy and flora alike crossed into Gillray's grotesques and eventually the sequential comic page.