1 4 ARKIV FÖR BOTANIK. BAND N. N:0 1. 



V. praecipue superne nigricante, lineari-oblonga, circiter 1,2 5 

 mm. longa, cum retinaculo subsequilata, obtusa munitum. 

 Caudiculse descendentes, circiter 0,5 mm. longse, latiusculae, 

 apice valde dilatat«. Pollinia leviter compressa, ovalia, cir- 

 citer 0,7 mm. longa, 0,45 — 0,5 mm. lata, basi rotundata, 

 apice oblique truncato-rotundata. Styli rostrum 8 — 10 mm. 

 longum, e basi satis tenui repente valde incrassatum, fere 

 usque ad basin bifidiim. lobis semiteretibus v. crasse foliaceis, 

 ovato-lanceolatis, 3 — i mm. latis, acutis, erectis (haud diver- 

 gent i bus). 



Argentina: Formosa (lO^VnOO. Kermes N:o 622.), 

 Entrerios, Conrepcion del Uruguay (Jun. 1875. Lorentz 

 X:o 184. j; Paraguay: in silvulis ad flumen Pilcomayo [Aug. 

 1906. RojAS X:o 407 (in Hassler, Plantoe paraguarienses).]. 



Cum sequente ssepe commixta est lijec species, sed jam foliis angusti- 

 oribus et praecipue floribus aliis perbene distincta fut jam monuit Grise- 

 BACH). Pauca tarnen specimina vidi; accuratiorem descriptionem conficiat, 

 cui plantam vivam examinare licet. 



Late est distributa et quidem in regione oecurrit aditu nunc pro magna 

 parte perficili at a botanicis nimis neglecta. — Verosiiniliter hue pertinet 

 'Araujia megapotamica 'Spreng.) Don >, quam in The Botanj^ of tlie Pilco- 

 mayo Expedition, 1890—91 [Transactions and Proceedings of the Bota- 

 nical society of Edinburgh. Vol. XX. Part 1 (1894j] commemorat J. 

 G. Kerr. 



A. megapotamica (Sprengel) G. Don. 



General History of the dichlamydeous plants. Vol. IV (1838). p. 149. 



Physianthua megapotamicus C. Sprengel, Systema vegetabilium, Cunc 

 poster. (18-27^, p. 112.^ 



Arauja fusca Grisebach, Svmbola» ad Floram argentinarn (1879), 

 p. 232. 



Lagenia megapotamica (Sprengel) Fournier in Flor, brasil. fasc. 

 XCV 1I88.5). p. 2)94. — Malme, Die Asclepiadaceen des Regnell'schen Her- 

 bars (1900, p. 75. 



Icones: Fournier, 1. c, tab. 85; Malme, 1. c, tab. 3, 

 fig. 8 (flos, retinaculum etc.). 



Frutex volubilis. ramis primum albopuberulis, dein gla- 

 bris, internodiis usque 15 cm. longis. Folia longepetiolata, 

 petiolo 2—4 cm. longo, triangularia v. oblongo-triangularia, 

 hastata, auriculis latis, rotundatis, vulgo 5—8 cm. longa, 

 supra basin 4—8 cm., medio 1—3,5 cm., rarius usque 4,5 cm. 

 lata, basi truncata, rarius leviter cordata, sinu apertissimo, 

 apice acuminata, primum leviter albo-puberula, mox glabra. 



* Descriptio brevissima Iutpc est: Physianthus megapotamicus*. Ph. 

 volubilis glaber. foliis sagittato-cordatis acuminatis, pedunculis Ifloris, 

 lobis coronae denticulatis. Rio grande. Sello. > 



Specimen originale vidi in herb. Musei berolinensis. 



