118 MELANTHACEAE (BUNCH-FLOWER FAMILY) 



Anthers confluently 1 -celled, cordate or reniform. 



Stems from a bulb; perianth-segments with gland or spot near the base 3. Zygadenus. 

 Stems from a rootstock; perianth-segments not gland bearing . . 4. Veratrum. 



1. XEROPHYLLUM Michx. 



Stem from a bulbous base, bearing a compact raceme of showy white 

 flowers, and thickly beset with needle-shaped leaves, the upper of which are 

 reduced to bristle-like bracts; those from the root very many in a dense tuft. 



1. Xerophyllum tenax (Pursh) Nutt. Gen. 1: 235. 1818. Stems 6-10 dm. 

 high: leaves often 5-8 dm. long: flowers white; pedicels 2-4 cm. long: perianth 

 scarcely equaling the stamens; segments oblong, 8-10 mm. long, 5-7-nerved: 

 capsule cordate-ovate, 6-valved, the abruptly acute cells separating and then 

 dehiscing. Montana, possibly Wyoming, and west to Oregon. 



2. TOFIELDIA Huds. FALSE ASPHODEL 



Mostly tufted, with fibrous roots, and simple stems leafy only at base, bear- 

 ing small flowers in a close raceme. Leaves linear, grass-like. Ours has stem 

 and inflorescence pubescent, and pedicels fascicled. 



1. Tofieldia intermedia Rydb. Bull. Torr. Bot. Club 27: 528. 1900. Stem 

 slender, viscid-pubescent above: leaves linear: raceme short, few-flowered: 

 flowers yellow: sepals obovate, 4-5 jnm. long: petals narrower and longer: 

 capsule ovoid: seeds unappendaged. T. glutinosa. Wyoming and far north- 

 ward and westward. 



3. ZYGADENUS Michx. 



Glabrous herbs, with leafy or somewhat scape-like stems from a tunicated 

 bulb, and long narrow keeled leaves. Flowers greenish-yellow or nearly white 

 in a terminal raceme or panicle. Perianth withering-persistent; the segments 

 with a glandular spot near the base. Stamens free or attached to the base of 

 the segments. Capsule 3-celled, dehiscent to the base. Seeds numerous, ob- 

 long or linear, angled. (Toxicoscordion and Anticlea, c. f. Bull. Torr. Bot. 

 Club 30: 272-3. 1903.) 



Gland obcordate; base of ovary adnate to the perianth 

 Gland obovate or semiorbicular; ovary free. 



Perianth-segments more or less clawed; filaments attached to the 



base of the segments. 



Flowers small; leaves narrow; gland orbicular . . . . 2. Z. yenenosus. 

 Flowers larger; leaves broader; gland semiorbicular . . . 3. Z. intermedius. 

 Perianth-segments not clawed; filaments free . . . . . 4. Z. Nuttallii. 



1. Zygadenus elegans Pursh, Fl. Am. Sept. 241. 1814. Bulb ovate: stem 

 2-8 dm. high: leaves glaucous, 4-12 mm. broad: raceme simple or sparingly 

 branched below, often few-flowered: bracts ovate-lanceolate, usually pur- 

 plish: perianth adnate at base; segments broad, greenish, 8-10 mm. long; the 

 inner abruptly contracted to a broad claw; gland obcordate: styles 4 mm. 

 long or more: seeds oblong, angular, 4 mm. long. (Z. dilatata Greene, PI. 

 Baker. 1: 51. 1901; Z. coloradensis Rydb. Bull. Torr. Bot. Club 27: 534. 

 1900.) The whole Rocky Mountain region from Colorado northward. 



2. Zygadenus venenosus Wats. Proc. Am. Acad. 14: 279. 1879. Bulb 

 elongated-ovoid: stem slender, strict, 1-5 dm. high: leaves narrow, 4-6 mm. 

 broad, scabrous on margin and midrib, with scarious sheathing base (except 

 the uppermost): raceme simple, short, with narrow scarious bracts: perianth 

 free from the ovary; segments triangular-ovate to elliptic, obtuse or acutish, 

 4-6 mm. long, all abruptly contracted to a short-glandular claw; the blade 

 rounded or subcordate at base; the gland with a well-defined irregular margin: 

 stamens somewhat adnate to the claw: pedicels suberect in fruit: capsule 

 8-12 mm. long: seeds 3-5 mm. long. (Z. gramineus Rydb. 1. c.) Northern 

 Wyoming and Montana and west to the Pacific States. 



