CUSCUTACEAE (DODDER FAMILY) 389 



(3-8) few-flowered umbels: flowers lurid-purplish: hoods only half the length 

 of the anthers, erect, strongly angulate-toothed at the front; the tip of the 

 erect subulate horn exserted. Dry sandy soil; from Wyoming and Colorado 

 to Arizona and Texas. 



9. Asclepias verticillata L. 1. c. 217. Stems 3-6 dm. high, slender, very 

 leafy: leaves mostly in whorls of 3-6, or some scattered, filiform-linear, with 

 revolute margins: umbels numerous, small, many-flowered, on peduncles 

 longer than the pedicels: corolla greenish-white; hoods white, broadly ovate 

 and entire, with somewhat auriculate involute base, barely equaling the 

 anthers, much shorter than their elongated-subulate, falcate-incurved horn. 

 In dry soil; from New Mexico and Colorado to Nebraska, and eastward across 

 the continent. 



10. Asclepias galioides H.B.K. Nov. Gen. & Sp. 3: 148. 1815. Glabrous, 

 except the minutely pubescent stems and pedicels; stems erect, 3-5 dm. high 

 from a horizontal rootstock: leaves erect or spreading, in whorls of 2-6, nar- 

 rowly linear, 5-8 cm. long, the margins revolute: peduncles longer than the 

 pedicels and shorter than the leaves; umbels 19-26 mm. in diameter; flowers 

 greenish-white: corolla-segments 4 mm. long; hoods as high as the anthers, 

 broadly rounded at the summit, dorsally hastate-sagittate, the ventral mar- 

 gins slightly involute, entire; horn arising from the base of the hood, long- 

 exserted over the anthers: anther- wings minutely notched at the base: folli- 

 cles erect on erect fruiting pedicels, attenuated, 5-7 cm. long, glabrous or 

 nearly so. Kansas to Colorado, Arizona, and Mexico. 



11. Asclepias pumila (Gray) Vail, in Brit, and Br. Fl. 3: 12. 1898. Stems 

 4-25 cm. high, tufted, from a woody root: leaves numerous, crowded, some- 

 times obscurely whorled, filiform-linear, 2.5-5 cm. long, smooth or minutely 

 roughened, the margins revolute: umbels 2-several, short-peduncled, few- 

 flowered; pedicels filiform, puberulent, 6-9 mm. long: corolla greenish-white, 

 its segments oblong, 3-4 mm. long; hoods white, erect, oblong, entire, equal- 

 ing the anthers, shorter than the slender incurved horn: follicles erect, on 

 erect fruiting pedicels, narrowly spindle-shaped, 3-5 cm. long, finely puberu- 

 lent. Dry plains; South Dakota and Wyoming to Arkansas and New Mexico. 



3. ASCLEPIODORA Gray 



Low and stout perennial herb, often decumbent. Flowers large. Corolla- 

 lobes ovate, greenish. Follicles usually bearing some scattered, soft-spinulose 

 projections, on recurved or sigmoid pedicels. Distinguished from Asclepias 

 by the hood bearing a crest instead of a horn. 



1. Asclepiodora decumbens (Nutt.) Gray, Proc. Am. Acad. 12: 66. 1876. 

 Scabrous-puberulent : leaves lanceolate to linear, tapering to the apex: umbels 

 solitary: corolla depressed-globular in bud, hardly twice the length of the 

 yellowish or dark purplish hoods, which overtop the somewhat depressed 

 anther-column: anther- wings salient, especially at the broader and strongly 

 angulate upper portion; pollinia pear-shaped, short-caudicled. From Utah 

 through Colorado and New Mexico to Texas and Arkansas. 



96. CUSCUTACEAE Dumort. DODDER FAMILY 



Parasitic plants with slender, thread-like, yellowish or reddish stems which 

 twine dextrorsely about the vegetative organs of the host plant and invade 

 its tissues by means of suckers. Leaves and bracts reduced to small scales 

 of the same color as the stems. Flowers small, cymose-clustered, mostly 

 white, 5 (rarely 4)-merous. Calyx cleft or parted. Corolla globular, urn-shaped, 

 bell-shaped, or somewhat tubular. Stamens inserted in the throat of the 

 corolla above as many scale-like crenulate or lacerate appendages. Ovary 



