WOOTON AND STANDLEY FLORA OF NEW MEXICO. 507 



Hoods of the crown not corniculate, or very 

 obscurely so. 

 Leaves mostly scattered, not densely 

 tomentose beneath ; flowers 

 greenish; anther wings nar- 

 rowed below 4. Acerates (p. 508). 



Leaves opposite, densely tomentose 

 beneath; flowers dark purple; 

 anther wings not narrowed be- 

 low 7. Gomphocarpus (p. 513). 



Hoods of the crown aristate or cornieulate- 

 appendaged within. 

 Hoods short, not surpassing the stamens, 

 or if long much broader below, 



never constricted at the base. . . 5. Asclepias (p. 509). 

 Hoods long, erect, much surpassing the 

 stamens, laminately expanded 

 below, narrow at the summit, 

 mostly bicorniculate 6. Podostemma (p. 512). 



1. VINCETOXICTJM Walt. Angle-pod. 



Herbaceous twining pubescent perennial from a slender rootstock; leaves opposite, 

 sagittate-cordate; flowers greenish, in small clusters; sepals lance-elliptic, green; 

 corolla narrowly campanulate, the lobes as long as the tube, oblong, obtuse; crown 

 nearly equaling the column, entire or barely undulate, inserted at the base of the 

 short column and connected with it by 5 adnate crests, free at the 2-toothed or entire 

 apex; pollinia obliquely inserted on broad winged caudicles; follicles ovoid, 3 cm. 

 long or more, puberulent. 



1. Vincetoxicum productum (Torr.) Vail, Bull. Torrey Club 26: 431. 1899. 



Gonolobus productus Torr. U. S. & Mex. Bound. Bot. 165. 1859. 



Type locality: "Banks of Rock Creek," "Valley of the Limpio, and along the 

 Rio Grande," Texas. 



Range: Western Texas to southern Arizona and southward. 



New Mexico: Organ Mountains; Mesilla Valley; Gray. Moist ground, in the 

 Lower and Upper Sonoran zones. 



2. PHILIBERTELLA Vail. 



Herbaceous twining perennials with opposite leaves and mostly fragrant flowers in 

 axillary umbels; calyx small, 5-lobed, the lobes acute; corolla campanulate or rotate, 

 a shallow entire or undulate ring forming an outer crown in its throat, the lobes 5, 

 longer than the tube, the inner crown of -5 turgid, fleshy or hard scales or flattish 

 appendages attached in a circle at the base of the sessile or slightly stalked column, 

 forming a hollow, entire or undulate, spreading surface near the level of the conical 

 stigmas; follicles naked, slender. 



key to the species. 



Column conspicuous; peduncles much shorter than the crispate 



leaves; stems cinereous 1. P. crispa. 



Column inconspicuous or none; peduncles equaling or surpassing 



the leaves, these aol crispate; stems glabrous or pubescent. 



Stems pubescent; flowers numerous in each umbel, white; 



Leaves cordate ovate to subsagittate 2. /'. cynanchoidea. 



Stems glabrous or nearly so; flowers few, reddish; leaves 



limar 8. P. heU rophyUa. 



