1958] 



THE BOTANY OF THE GUAYANA HIGHLAND PAKT III 



133 



rueulose by the persistent bases of the short stiff hairs; leaves (4—) 6 (-7) r 

 vertieillate or become subvertieillate, crowded, chartaceous; petioles short, less 

 than 1 mm long ; blades filiform, acute at base and apex, revolute at the margins, 

 3-6.5 cm long, about 0.5 mm wide, or 1-2.5 (-4) mm wide when the margins 

 are spread out, roughened with a few minute stiff hairs at the apex on the upper 

 side, otherwise glabrous or sometimes weakly hirtellous along the midrib on the 

 under side and elsewhere, the midrib sunken on the upper side, the secondary 

 nerves numerous, spreading at right angles from the midrib, faint to rather 

 pronounced, foliar glands scattered along the midrib on the upper side or lack- 

 ing (not developed) ; flowers lacking; axis of the infructescence 4—7 cm long, the 

 scars scattered; fruits few, usually 1 or 2, the pedicels becoming incrassate, about 

 3 mm long, the calyx deciduous, the lobes about 2 mm long, glabrous in age, 

 calycine squamellae irregularly distributed; mericarps free (earlier united at 

 the apex), erect, slender, lightly torulose, 6-11 cm long, 3 mm thick, glabrous 

 or puberulous at the apex, the disk remaining as a low collar at the base of the 

 fruit; seeds (not fully matured) subscaphiform, about 8-9 mm long, 2 mm 

 broad, brownish, puberulent or densely pubescent, the coma sessile, 1-2 cm 

 long, tawny. 



Type: J. J. Wurdack (& J. V. Monachino 40975, Rio Parguaza, Estado Boli- 

 var, Venezuela, locally frequent on Cerro Negro Peron, an E-W crystalline range 

 on right bank of river just below El Carmen (about 50 river km from mouth), 

 elev. 120-350 m, seen also at Pieclra Mapollos, Dec 27, 1955, slender woody vine 

 with abundant latex, fruit brown (holotype NY). 



Paratypes: VENEZUELA: Amazonas: Bassett Maguire $ Celia K. Maguire 35167, 

 Serram'a Yutaje, Rio Manapiare, frequent in scrub forest on northwest ridge, elev. 1400 m, 

 Feb 11, 1953, perennial subshrub with sharply angled stems. B. Maguire 4' C. K. Maguire 

 35230, Serrania Yutaje, Rio Manapiare, frequent along left fork of Cano Yutaje, elev. 1250 m, 

 Feb 12, 1953. 



The type of M. filifolia does not show foliar glands; the seeds (fruit not fully 

 matured) are only faintly puberulent. The collections from Yutaje, 35167 and 

 35230, are more erect in habit ; they clearly show glands along the midrib ; the 

 seeds are densely pubescent. Some of the leaves in 35167 are broader with sec- 

 ondary nerves expressed beneath and mor ascending. The difference in seed 

 indumentum is particularly disturbing, but it seems best at present to regard 

 it, as well as the difference in habit of the plant, glands, leaf width, venation, 

 and hirtellousness, as mere variation. Although flowers are lacking in the pres- 

 ent material, M. filifolia can be placed with almost certainty in the subgenus 

 Exothostemon. Hitherto, the only species in the subgenus with vertieillate leaves 

 was M. benthamii (A. DC) K. Sch., easily distinguished from M. filifolia by its 

 oblanceolate, broader, proportionately shorter, thicker, coriaceous leaves with 

 obscure secondary nerves and fewer (mostly 4) in each whorl. 



Mandevilla lancifolia var. calva Monachino, var. nov. 



Haec varietas a var. lancifolia recedit caulibus omnino glabris, foliis lati- 

 oribus, venis secundariis numerosioribus erectioribusque, et sepalis eciliatis. 



Vine or reclining subshrub, the stem moderately thick, lightly angled, com- 

 pletely and perfectly glabrous, brown becoming grey; leaves opposite, firmly 

 chartaceous or subcoriaceous ; petiole about 5 mm long, glabrous; blade lanceo- 

 late to oblong, rounded at the base, obtuse or narrowed and minutely apiculate 

 at the apex, 2.5-8 cm long, 0.8-1.7 cm wide, glabrous, the midrib depressed on 

 the upper side, lightly raised beneath, the secondary nerves numerous, spreading 



