948 ASCLEPIADACEAE 



gins infolded, with an auriculate tooth or lobe below the middle : horn subulate, arising 

 from the middle of the hood, incurved over the anthers : anther-wings auriculate-spread- 

 ing : follicles erect, 9 cm. long, slender-fusiform, minutely puberulent : seeds 4 mm. long : 

 coma 2 cm. long. 



In wet pine lands, near Apalachicola, Florida. Summer and fall. 



26. Asclepias cinerea ^Vult. Stems glabrous or nearly so, slender, erect, 3 dm. liigh 

 or more, sometimes slightly pubescent in lines : leaves opposite, 3-9 cm. long, rather dis- 

 tant ; blades narrowly linear or filiform : umbels 2-6, terminal and lateral, 3-8-flowered : 

 peduncles short : corolla purplish on the outside ; lobes oval, 5 mm. long, with whitish 

 scarious margins, ash-colored within : hoods much shorter than the anthers, whitish and 

 purple-keeled, slightly pendulous at the base over the short or obsolete column, truncate 

 at the apex, the involute ventral margins extended into acute erect ascending lobes or 

 angles : horn erect, included, broadly triangular, inserted about the middle of the hood : 

 follicles slender-fusiform, 8 cm. long, 5-6 mm. wide, attenuated at each end, erect on erect 

 pedicels, glabrous : seeds 5 mm. long, with a thick coriaceous margin : coma 3 cm. long. 



In rather dry pine lands, South Carolina to Florida. Summer. 



27. Asclepias Emoryi (Greene) Vail. Stems minutely and cinereously pubescent 

 with somewhat curved hairs, becoming less so with age, 3-4 dm. high or more, Horiferous 

 for nearly their whole length : leaves 4-10 cm. long ; blades elongated-lanceolate, acute, 

 tapering to the short margined petioles : umbels small, sessile or very short-peduncled, 

 4-6-flowered : corolla-lobes 6-7 mm. long, apparently greenish white : hoods white, 5 

 mm. high and twice as high as the anthers, fleshy, adnate only at the very base, solid at 

 the back and below the ventral margins free to near the base, spreading at the summit 

 into a short open 2-lobed lamina : horn broad, fleshy, subulate, inflexed, arising from 

 the apex of the hood, wrinkled at the insertion, downcurved, barely exserted : accessory 

 processes minute near the base of the hood : anther-wings semi-rhomboid, narrow, ob- 

 tusely angled below the middle, rounded at the base, tapering above, entire or nearly 

 so : follicles 5.5 cm. long, erect on recurved pedicels lanceolate-fusiform, puberulent : 

 seeds 7 mm. long, round-oblong, granulose : coma 2-2.5 cm. long. [Podosteinma Emoryx 

 Greene. ] 



On plains or prairies, southern Texas. Summer. 



28. Asclepias Lindheimeri Engelm. Stems minutely puberulent or minutely sca- 

 brous, simple or branched, rather stout, 3-4 dm. high, decumbent or ascending : leaf- 

 blades deltoid, broadly oval or oblong-oval, some of the upper ones narrower and lanceo- 

 late-oblong, 5-9 cm. long, obtuse or commonly broadly rounded at the apex, tapering at 

 the base or each abruptly or truncately contracted into a (1-2 cm. long) flat petiole: 

 umbels abundant, the upper sessile, the lower on peduncles 5 mm. long or less, few- to 

 many -flowered : corolla-lobes greenish, 1 cm. long : hoods white, over twice the lieight of 

 the anthers, slender at the stalked base, dilated above into a 3-lobed or obscurely 4-lobed 

 lamina : horn attached to the solid keel-like portion of tiie hood, slender, attenuate, in- 

 flexed, scarcely exserted, the accessory process much shorter, erect, obtuse : anther-wings 

 semi-ovate, the rounded base broader than the tapering upper portion, minutely notched at 

 the middle : accessory 5 processes ver}- broad, with acutish angles grasping the base of the 

 anther-wing : follicles ovate-lanceolate, long-attenuated, 8-10 cm. long, erect on recurving 

 pedicels, puberulous : seeds 6 mm. long, round-ovate: coma 3-3.5 cm. long. 



On plains or prairies, Texas to New Mexico and Mexico. Summer and fall. 



29. Asclepias obovata Ell. Stems cinereous with soft pubescence or tomentum, 

 rather stout, erect, 4 dm.-l m. high : leaves opposite ; blades oval, oblong, or some of 

 them obovate, 3-10 cm. long, 1.5-4.5 cm. wide or more, mucronate-apiculate at the apex, 

 rounded or subcordate at the base, tomentose, at length glabrate or nearly so, undulate on 

 the margins, the midvein broad and conspicuous : umbels 2-6, lateral in the upper axils, 

 nearly sessile : corolla-lobes greenish yellow, oblong, about 1 cm. long : column very short : 

 hood purplish, erect, 7 mm. high, much exceeding the anthers, truncate at the apex, dor- 

 sally bigibbous at the base by reason of an excrescent fold on each side, the thin ventral 

 margins rounded, involute and meeting for nearly their whole length, a pair of broad short 

 fleshy processes or auricles at the base within on either side of the anther-wings : horn 

 narrowly falcate, fleshy, horizontally exserted for nearly half its length, arising from the 

 base of the hood : anther-wings bicorniculate at the salient basal angle : follicles 8-11 cm. 

 long, erect on erect fruiting pedicels, obtuse at the tapering apex, tomentulose : seeds 8 

 mm. long, thin, minutely pitted : coma 3 cm. long. 



In dry grounds, mainly near the coast, South Carolina to Florida and Texas. Summer. 



