46 Mora of the Palouse Region 



S. sessilifolia Nutt. Rootstocks slender: stems 30-60 cm. tall, smooth: 

 leaves broadly lanceolate, acuminate, flat, sessile, pubescent beneath, 10-15 

 mm. long: raceme open, 2-5 cm. long, 5-10-flowered: perianth-segments 

 spreading, lanceolate, 4 mm. long: stamens shorter than the styles. Com- 

 mon in moist copses. 



71. UISPORUM. 



More or less pubescent herbs with slender rootstocks: stems 

 branching, scaly below, leafy above: leaves alternate, somewhat 

 unsymmetrical, sessile or clasping: flowers terminal, drooping, 

 whitish or greenish-3-ellow, solitary or few in simple umbels: per- 

 ianth-segments 6, narrow, equal, separate: stamens 6, hypogynous: 

 ovary 3-celled; ovules 2 or sometimes several in each cavity. 



D. trachycarpum B. & H. Stems branched, 30-50 cm. tall, the branches 

 pubescent: leaves oblong or oblong-ovate, long-acuminate, sessile and half- 

 clasping, 5-7 cm. long, glabrous: flowers solitary or in pairs, yellowish- 

 white, on more or less curved pedicels, 5-8 mm. long: perianth campanulate, 

 the segments narrow, oblong or oblanceolate, 10-12 mm. long: berry pyriform- 

 globose, 6-8 mm. in diameter, roughened with minute shallow pits. In 

 woods, Thatuna Hills. 



72. STREPTOPUS. 



Herbs with stout or slender rootstocks: leaves thin, 

 sessile or clasping, alternate, many-nerved: flowers solitary or two 

 together, axillary, slender-peduncled, greenish or purplish, small, 

 nodding; peduncles bent or twisted at about the middle: perianth 

 somewhat campanulate, its segments 6, recurved or spreading, the 

 outer flat, the inner keeled: stamens 6, hypogynous: ovary 3-celled; 

 ovules numerous, in two rows in each cavity. 



S. amplexifolius DC. Stems branched, about 1 m. tall, from horizontal 

 creeping rootstocks, glabrous except at the base: leaves ovate, acuminate, 

 cordate and clasping at base, 5-12 cm. long, usually glaucous, especially be- 

 neath: flowers solitary in the upper axils; pedicels bent at the base and gen- 

 iculate in the middle, so that the flower is concealed by the leaf: perianth 

 narrowly campanulate, the segments greenish, lanceolate, acuminate, 

 strongly curved outward: anthers acuminate: berry oblong-globose, red, 

 about 1 cm. in diameter. Moist woods, Thatuna Hills. 



73. TRILLIUM. 



Glabrous erect unbranched herbs, with short scarred root- 

 stocks: leaves 3 in a whorl at the summit of the stem just under 

 the sessile or peduncled, solitary, bractless flower: perianth of 

 two distinct series of segments, the outer 3 (sepals) green, the 

 inner 3 (petals) white, pink, purple or sometimes greenish: stamens 

 6, hypogynous: ovary sessile, 3-6-angled or lobed; ovules several 

 or numerous in each cavity. 



