1957} 



THE BOTANY OF THE GUAYANA HIGHLAND— PART II 



353 



and longer hairs on the lower surface, smaller distinctly elevated petiolar glands, 

 and much larger flowers with alae about 12 mm long. S. lateralis was described 

 from a Spruce collection from Manaos. Such a disjunct known distribution is also 

 evident in S. uniflora Oort, known from several collections in the Guianas and 

 also from Manaos {Vie 8886, fide Sandwith in litt., and Ducke 1769, 23-LX-1945). 



Securidaca speciosa Wurdack, sp. nov. 



Frutex scandens; ramuli tereteSc, aeque cum petiolis inflorescentiis pedicel- 

 lisque pilis parvis patentibus modice et persistente induti. Folia elliptico-ovata 

 apice obtusa minute apiculataque basi obtusa vel subcordata in sicco plerumque 

 conduplicata infra inflorescentias 4.5-8.5 x 2.5-6 cm apud inflorescentias minora 

 coriacea marginibus non incrassatis, supra nitida glabra (praeter nervum medium 

 sparse hirsutulum),^ subtus pallidiora nervo medio persistenter hirsutulo venulis 

 superficieque statu juvenili sparse hirsutulis glabrescentibus, nervis primariis 

 utrinque 6-8 reticulo supra et subtus manifesto; petiolus 3*5 mm longus basi 

 glandulis inconspicuis 0.2 mm diam. Paniculae terminales speciosae ramis 7-45 

 cm longis; bracteae valde caducae parvae 1.3-1.7 mm longae. F lores purpurei 

 (in sicco albidi). Sepala exteriora late ovata apice obtusa vel rotunda ciliolata 

 extus sparse strigulosa intus glabra, uno postico 4.3-4.8 x 3-3-3.6 mm duobus 

 anticis 3.4-3.8 x 2.8-3-4 mm; alae ovato-orbicularies 11-14 x 3.5-10.5 mm apice 

 leviter retusae, ungue breve, marginibus ciliatis cetero glabris. Petala lateralia 

 obovato-spathulata apice late obtusa 9-10x4-5.2 ram intus basim versus sparse 

 hirsutula atque sparse ciliolata extus glabra dente laterali inconspicuo; carina 

 tota 10-11 mm longa ungue 2-3 mm longo ciliolata intus marginem basalem versus 

 hirsutula, crista parva 1 mm alta 2-2.3 mm lata subintegra irregulariter denticulato- 

 crenata. Staminum vagina 6-6.7 mm longa basim versus ciliolata et intus basim 

 marginemque versus hirsutula; filamenta libera 3—3.5 mm longa; antherae 0.8-1.3 

 mm longae apice acutae vel brevicaudatae. Ovarium aeque cum ala glabra, stylo 

 ad medium aut supra gradatim geniculato (angulo ultimo 90°) glabro 7-10 x 0.6-0.7 

 mm, stigma 1-1.2 mm latum. Fructus maturus non visus, fructu maxime immaturo 

 toto glabro. 



HOLOTYPE: scandent shrub, frequent in open rocky places, Raudal Ouraima, 

 Rio Paragua, Edo. Bolivar, Venezuela, elev. 175 m, Jan. 20, 1952. Maguire 

 33152 (NY). Paratype: woody vine with purple fls, riverine woodland at portage, 

 Raudal Ouraima, Dec.' 10, 1951 Maguire 32717. 



S. speciosa is closely related to the widespread S. diversifolia (L.) Blake and 

 resembles that species in leaf nervation; the Ouraima species may be differentiated 

 by its glabrous leaf surfaces, somewhat smaller carinal crest, and completely 

 glabrous ovary and ovary wing. In general aspect S. speciosa is not unlike S. 

 marginata Benth., but the persistent stem pubescence, non-incrassate leaf margins, 

 glabrous ovarial wing, and distinctly cristate keel separate it from that species; 

 the glabrescent branches, smaller leaves, and ecristate keel differentiate S. retusa 

 Benth. 5. pendula Bonpl. (S. complicata H-B.K.) differs at least in the pubescent 

 narrower alae and smaller leaves; Bennett in his key in Flora brasiliensis cited 

 S. complicata as having an ecristate keel, but both the H.3.K. description and 

 type photograph (F 13089) indicate the presence of a crest. 



BEGONIACEAE 14 



The Begoniaceae are so poorly represented in the Guayana Highland that few 

 conclusions can be drawn from their distribution. However, these few species, 



14 3y Lyman B. Smith and Bernice G. Schubert. 



