48. Geranium tetragonum L. f., Suppl. Pl.: 305. 1782. ≡ Pelargonium tetragonum (L. f.) L’Hér. in Aiton, Hort. Kew. 2: 427. 1789. – Geranium quadrangulare Thunb. [nom. nud.]. Lectotypus (designated by ALBERS et al., 1995: 344): SOUTH AFRICA: Thunberg s.n. (UPS-THUNB n° 15663!; isolecto-: G-PREL [G00818045, G00818046, G00818047, G00818048]!, UPS-THUNB n° 15662 image seen). Notes. – Geranium tetragonum was based on a Thunberg specimen from the Cape. ALBERS et al. (1995: 344) designated a specimen in UPS-THUNB as the lectotype. Four duplicates of this collection are also present in G-PREL: three in the Burman herbarium [G00818045, G00818046, G00818047] and one in the Houttuyn herbarium [G00818048]. The latter bears the name G. quadrangulare Thunb. in Houttuyn’s handwriting. The four G-PREL collections are duplicates of the original material and are here considered as isolectotypes.

Published as part of Wijnands, Dirk Onno, Heniger, Johannes, Veldkamp, Jan Frederik, Fumeaux, Nicolas & Callmander, Martin W., 2017, The botanical legacy of Martinus Houttuyn (1720 - 1798) in Geneva, pp. 155-198 in Candollea 72 (1) on page 176, DOI: 10.15553/c2017v721a11, http://zenodo.org/record/5721887