822 PROCEEDINGS OF THE AMERICAN ACADEMY. 
IIIl.—NEW DIOSCOREAS FROM MEXICO. 
By E. B. ULIne. 
Dioscorea pumicicola. Only g¢ plant seen. Stem slender, gl~ 
brous, dextrorsely twisted ; leaves cordate at base, deltoid or sub-trilobat 
lateral lobes rounded, median part ovate and blunt or abruptly acumina’© 
at apex, about 7-nerved, glabrous above, sparsely pubescent on the 
nerves beneath; flowers arranged in 3-d-flowered cymules, which a‘ 
short-pedunculate, and situated at the angles of the slender rhachié ee 
anthers subsessile, triangularly disposed at the centre of the open caly— 
panulate greecnish-brown corolla. 
Leaves 8 to 12 cm. broad, little longer than wide. Petiole 4 or 5 er. 
long, puberulent. Rhachis slender, angulate-flexuous, puberulent, 1 to | Aa ng 
dm. long. Cymules 4 to 8 mm. apart, subsessile or on short peduncles: 
Flowers’ sessile, 8 mm. wide, with orbicular corolla-lobes, the inner 
whorl shorter. Anthers very minute.— This species is intimately 7 
lated to D. macrostachya and D. spiculiflora, its inflorescence and flowe~ 
being esseutially the same as the latter, but it differs radically from hier 
in its lobed leaves and pubescence. 
Morelos, lava beds near Cuernavaca; C. G. Pringle no. 7227 3, 189° 
D. oaxacensis, Uline in Engl. & Prantl, Nat. Pflanzenf. Nachtr. ~ 4 
II, 5, p. 86, without characterization. — Glabrous, glaucous; leave’ — 
chartaceous, cordiform with wide sinus, 9-nerved, exterior nerves @F 
both sides more or less forked; ¢ racemes elongate, simple; rhachise* | 
angulate ; flowers shortly pedicellate, in 2—3-flowered rather remote fer: 
cicles (rarely solitary), segments of the subrotate 6-parted perian’ ht 
oblong, rather acute, the interior ones slightly narrower; fertile yous 
3, subcentral, a little shorter than the segments of the corolla, strong id 
=. 
ineurved, anthers extrorse in the bud, sterile filaments 3, very er fle’. 
entire, sometimes bearing effete anthers. 
tem compressed, angular, sinistrorsely twisted. Leaves soitiend 25 ey 
to 4 cm. wide, acuminate. Petioles about 2 cm. long. Racemes as lon: Ze 
as 1.5 dm. Floral fascicles 4 to 12 mm. distant, shortly pedunculat oy 
Flowers 6 mm. wide, on short slender pedicels; corolla-segments- oes 
pe unequal, greenish-yellow. 
n. D. Ane ome dg Mart. & Gal. Bull. Acad. Brux. ix. pt» 2) 7 " : 
nth. 
391 (1843), not B 
Mexico near Svea: altitude 1,800 to 2,050 m., E. W. Nelson, ©” 
178 
6, i ~ tenis i Cry 08 to . plant, in 1894. The only other sper : 
ie eae th ae See 
np WERE pa 
