324 PROCEEDINGS OF THE AMERICAN ACADEMY. 



beneath, 2-3 inches in length, about the same breadth : flowers of 

 the staminate plant in slender compound racemes ; the latter scarcely 

 pedunculate, either solitary in the axds or borne at the successive 

 nodes of the leafless ends of the stem ; branches of the racemes numer- 

 ous, about 5-flowered, the uppermost reduced and fewer-flowered : 

 pedicels \ line long: bracts lance-linear, acuminate: perianth cam- 

 panulate, pale yellow; segments obovate, rounded at the ends, 1^ 

 lines in length : stamens 3 ; filaments slender ; rudiments none : fertile 

 racemes axillary, short-peduncled, in fruit 2-3 inches in length : fruit 

 suborbicular, retuse, 3^ lines in diameter (immature). — Collected 

 on grassy slopes of barranca near Guadalajara, 7 September, 1893 

 (no. 4526). 



D. hirsuticaulis. Pubescent-hirsute throughout with crisped 

 white hairs : stem elongated, twining : leaves deltoid-ovate, acu- 

 minate, entire, cordate with an open sinus, about 9-nerved, 2-3 

 inches long, nearly as broad; petioles 8 lines in length: racemes of 

 the staminate plant slender, simple, about \\ inches in length upon 

 peduncles perhaps half as long, solitary in the axils or borne at the 

 successive nodes of the nearly leafless ends of the stems ; pedicels 

 but \— \ line in length : perianth campanulate, a line in diameter ; 

 segments ovate-oblong, obtuse : stamens only 3, filaments short and 

 straight : inflorescences of the female plant axillary, solitary, in fruit 

 \\ inches in length, \ inch in diameter: fruit stramineous, broadly 

 elliptic, smooth, 4| lines in length, 2>\ lines in breadth, reflexed and 

 very densely imbricated. — Collected under dry ledges, barranca of 

 Tequila, 14 October, 1893 (no. 4572). 



D. plumifera. Glabrous: stems twining : leaves thin, ovate acu- 

 minate, entire, cordate with a broad sinus, 7-11-veined, slightly 

 paler beneath, 2^—3 inches long, 2 inches broad : staminate flowers 

 yellowish green, 2^- lines in diameter, borne in long slender feathery 

 panicles ; the latter geminate at the axils, 4 inches in length, \ inch 

 in diameter ; the numerous short lateral brandies about 3-flowered ; 

 pedicels |— 1 line long, very slender : bracts lance-linear, acuminate, 

 1 line in length : segments of the perianth oblong-lanceolate, obtuse : 

 fertile stamens 3, slender, not at all rigid or divaricate, alternating 

 with 3 rudiments: racemes of the fruiting plant short-peduncled, 

 densely flowered, 2 inches in length : fruit (scarcely mature) broadly 

 elliptic, 4 lines long, reflexed, imbricated. — Collected under cliffs, 

 barranca of Tequila, 14 October, 1893 (no. 4530;. 



D. militaris. A slender vine 2-4 feet in length : stem smooth, 

 from a small tuber : leaves rather distant, 3-lobed and halberd-shaped, 



