Copy of plate 16 from Testacea microscopica aliaque minuta ex generibus Argonauta et Nautilu...by Leopold von Fichtel and J.P.C.von Moll (New edition, Vienna, 1803). Inscribed below with captioning details. “Nautilus planatus var...[alpha, beta, gamma and iota] Peneroplis panatus...”
Each foraminifera [single-celled marine organisms with shells] in the illustration is reproduced under magnification or in section and at actual size. In modern taxonomy, varieties of Peneroplis planatus.