424 Vail : Studies in the Asclepiadaceae 



Asclcpias po'ouiis var. parvula (A. Gray) Proc. Am. Acad. 12 : 

 70. 1S76. 



Asclcpias nhca Hemsl. Biol, Centr. Am. 2: 325 and 4 : 69. 

 1 88 1-3. Not Linn. 1753. 



Pale gray-green throughout. Stem woody at the base, 3 dm. 

 high, or more, erect, pubescent, often branched above : leaves 

 short-petioled ; blades lanceolate or oblong-lanceolate, tapering at 

 each end, 4-6 cm. long, rather thick and coriaceous, glabrous or 

 minutely puberulent above, puberulent beneath on the veins and 

 revolute margins : peduncles 3-9, terminal and lateral, 1-4 cm. 

 long; umbels io-20-flovvered : corolla white, small; column 

 slender ; hoods hastately sagittate at the base, not exceeding the 

 anthers ; horn falcate, thin, exsertcd, inflexed over the anthers : 

 anther-wings narrow, entire at the salient base : follicles slender- 

 fusiform, tapering to each end, 7-9 cm. long, glabrous : seeds 7 

 mm. long, red-brown, very thin, glabrous ; coma 2-3 cm. long, 

 abundant. 



J * 



Mexican BoiDidary Survey, Head of Rock 'Creek, Bigelow, 

 July 7, \^12\ ^^ Nezv Mexico;' \Nx{g\\t\ Texas: Havard, Neally ; 

 Mexico: Palmer, no. 8 1 2. 



[no. 1684 in part] 



in the Herbarium of Columbia University, No. 1683, also of 

 Wright's collection, contains besides A, parvula some specimens 

 of A, longicornu Benth. (the plant since described as Podosteinma 



Vail. 



^P 



Stelmagonum ? Holtonii 



A low perennial herb. Root slender, vertical : stems slender, 

 twining above, granular-puberulent and thinly hirsute with stiff 

 spreading hairs, the lower portion with small corky-barked ridges : 

 leaves opposite, on slender, granulose-p^.iberulent and hirsute, 

 T. 5-2. 5 cm. long petioles; blades ovate-cordate, 3-4 cm. long, 

 1.5-2 cm. wide, acuminate at the apex, basal lobes rounded with 

 narrow open sinus, granular-puberulent and with a few scat- 

 tered short stiff hairs above, granular-puberulent and with 

 more numerous stiff hairs beneath, especially on the veins, mar-, 

 gins ciliate : flowers 4-7 in short -pedi.mcled bracteolate cymes : 

 peduncles axillary, 3 cm. long ; pedicels 4-5 mm. long, the brac- 

 teoles subulate, very small, persistent: calyx 5-parted to below 

 the middle, 2-1 mm. long, granular-puberulent and ciliate ; 

 segments acuminate, with an erect subulate gland in each sinus : 

 corolla campanulate, y-Z mm. long ? or more, 5-parted to a 



