667 



Vail : Studies in the Asclepiadaceae 



in herb. Kevv : Oaxaca, Gliiesbreght (also in herb. Kew). The 

 last two specimens are cited in Hemsley, Biol. Centr. Am. 2 : 329 

 under Roulinia Jacqjiini. 



Differing from R. nnifaria and R. racemosa in its more woody 

 stem and lighter green thicker leaves. It has the crown-segments 

 of R. racemosa but the pollinia of R. nnifaria. 



i 6. Rouliniella foetida (Cav.) 



Asclcpias foetida Cav. Ic. 2 : 45. //. ij8. 1793. 

 Cynanchuni foetidnni H.B.K. Nov. Gen. Sp. 3 : 202. 181 8 ? 

 Roulinia Jacqidfiii T)Q. Prodr. 8: 517. 1844. Excl. syn. 



A slender twining vine. Stems glabrous or with a narrow 

 puberulent line : petioles slender, 3—7 cm. long : leaves opposite ; 

 blades ovate or some of the smaller ones ovate-lanceolate, 5— ii 

 cm. long, acuminate at the slender apex, cordate at the base with 

 open sinus and rounded basal lobes, puberulent on the veins be- 

 neath : flowers 8-12 mm. in diameter in small sub-umbellate 

 clusters ; buds ovate : peduncles 

 minutely puberulent, 2-3 cm. 

 long, commonly shorter than 

 the petioles: calyx 1.5 mm. 

 long; segments linear-oblong, 

 acutish at the apex, minutely 

 ciliate, with a large gland in 

 each sinus : corolla 6-7 mm. 

 long, dull- greenish, fleshy, 

 glabrous on the outer surface, 

 whitish or cream color ? with 

 two raised puberulent callous 

 ridges or crests along the 

 upper portion within ; crown - 



segments white, very thin, 5, the lateral margins infolded and 

 adnate to the inner surface, the long ligulate apex very slender, as 

 long as the corolla segments or nearly so : anther-wings long and 

 narrow : pollinia oblong, on short broad pale yellow caudicles ; 

 corpuscle reddish, rounded at the apex, narrowet at the bifid base : 

 stigma barely conic, 5 -rayed : follicles angled and winged. Mature 

 follicles not seen, [Fig- ^O 



Mexico : Oaxaca, Ga/cotti, ijj8 (in herb. Kew) ; near 

 Oaxaca, alt. 1600 m., 1896, C. Conzaiti, 2iy ; Valley de Etla, 

 Sept. 1895, C. Ahmrcz, j68 ; Huitzo, alt. 1700 m., 13 Aug. 

 1897, C. Conzatti & V. Go)Lzalcs, jj6 (in herb. Gray). 



