665 



Vail : Studies in the Asclepiadaceae 



Fig. 



apex, 3-8 cm. long, grayish-green, thin : inflorescence sub-corym- 

 bose : peduncles 3-5 cm. long, 5-7-flowered : flowers sub-globose 

 in bud : calyx-segments slender, linear-lanceolate, 4-5 mm. long, 

 puberulent : corolla greenish-white, obtuse in the bud ; segments 

 somewhat crisped and revolute on the margin, a little longer than 

 the calyx : crown -segments 

 united at the base, quadrate, 

 3-lobed at the apex ; middle 

 lobe triangular, acutish or 

 obtuse, obscurely 3-toothed 

 at the apex, a little longer 

 than the infolded lateral 

 lobes : stigma nearly flat : 

 pollinia oblong ; caudicles 

 broad, with an orange-colored 

 spot along the upper margin : 

 follicles 10 cm. long, some- 

 what spongy when dry, 

 wrinkled, glabrous : seeds 7 



mm. long, glabrous, crenate along the apex: coma 2.5-3 ^^n- 

 long. {Fig. J.) 



Mexico : Mountains 24 miles northeast of Monclova, State of 

 Coahuila, September 1880; Palmer, 82^. 



4. Rouliniella racemosa (Jacq.) 

 Cynanchuin raceniosum Jacq. Select. Am. 'i\. pi. 5^. 1788. 

 Roiilinia racemosa Kuntze, Rev. Gen. PI. 422. 1891. 



A much branched twining vine. Stems angled, slender, gla- 

 rous except for a narrow pubescent line : leaves on petioles 2-4 



cm. long ; blades ovate-cordate, 

 6—9 cm. long, long-acuminate, 

 with broadly rounded basal 

 lobes and open sinus : inflor- 

 escence racemose, shorter than 

 the leaves : peduncles 4—7 cm. 

 long, 10— 20-flowered : flowers 

 5 mm. in diameter, sub-globose 

 in bud : calyx-segments lanceo- 

 late, acuminate, with a gland in 

 each sinus : corolla greenish- 

 white ; margins of the lobes 

 crisped : crown -segments united 

 at base, obtusely 3-lobed at the 

 twice or more longer than the 



Fig. 4. 



summit 



central lobe ligulate. 



