A new species of Argyreia from Sumatra (Convolvulaceae)

Frutex scandens. Caules in statu florigero foliis destituti, internodiis longis, usque ad 18 cm metientibus, in nodis ramulos laterales breves vel apicem versus inflorescentias emittentes. Ramuli laterales folia nonnulla vel inflorescentias gerentes, internodiis multo brevioribus vel brevissimis. Caules teretes vel juniores obscure angulati, griseo-brunnei, in sicco longitudinaliter hinc inde transversaliter rugosi, juniores pilis brevibus adpressis praediti, adultiores glabri, plusminusve verrucosi (lenticellati). Folia petiolata ; petiolo breviter et adpresse piloso ut in partibus junioribus caulis, supra sulcato, ad 6 cm longo; lamina ovato-oblonga, apice breviter acuminata, basi ± rotundata (vel in foliis junioribus late cuneata), nervis exceptis glabra, 11—15 cm longa, 5—6 cm lata; nervo mediano nervis lateralibus utrinque c. 4 et nervis secundariis ± parallelis subtus prominentibus supra impressis. Inflorescentiae in axillis foliorum delapsorum caulium primariorum vel ramulorum lateralium, primo casu umbellatocymosae, 4—8- vel usque ad c. 20-florae, secundo casu etiam umbellatoeymosae, sed praeterea in paniculam conjunctae. Pedunculi praesertim apicem versus applanati, 10—24 mm longi, adpresse pilosi, pilis ut in ramulis junioribus, apice umbellato-cymosi ; ramuli adpresse pilosi ; pedicelli 4—7 mm vel in flore centrali ad 10 mm longi, basi ± dense, apicem versus ± sparse adpresse pilosi. Sepala glabra vel prope basin extrinsecus sparse pilosa, exteriora duo late ovata apice rotundata vel paullo retusa, c. 6 mm longa; sepalum tertium paullo obliquum, elliptico-orbiculare, c. 6—6.5 mm longum, margine uno latere tenuiore; sepala duo interiora elliptico-orbicularia, c. 6.5 mm longa, marginibus tenuioribus. Corolla infundibuliformis, c. 3.5 cm longa, alba, limbum versus rosea vel violacea, limbo paullo lobato, c. 4—4.5 cm diam., fasciis mesopetalis glabris. Filamenta c. 10 mm supra basin corollae inserta, c. 20 mm longa, basi dilatata pilosa ; antherae linearilanceolatae, 5—6 mm longae. Stylus filiformis c. 27 mm longus, glaber; ovarium oblongo-ovoideum, glabrum, 4-loculare; stigmata globosa, papillosa. Discus annularis, integer, c. 1½ mm altus. Bacca ovoidea, c. 14 mm longa, violacea. SUMATRA, West Coast, Ophir district, N.-W. slope of Mount Talakmau, 900 m alt., H. A. B. Bünnemeijer n. 436, fl. April 25, 1917 (Climber in forest. Flowers white at base, violet above when young) ; W. slope of Mount Talakmau 600 m alt., H. A. B. Bünnemeijer n. 375, fl. April 24, 1917 (In forest. Flowers white, pink above; fruit violet; vern. name: akar katjan pariwo). Both specimens in herb. Buitenzorg; n. 436 is the typus florum; n. 375 is the typus foliorum et fructuum.