258 FLORA. 



the cavities not diverging, dehiscent to the base. Seeds oblong or linear, angled. 

 [Greek, referring to the two glands of some species.] About 10 species, natives oi 

 North America and Mexico, I in Siberia. 



Plant with a thick rootstock ; glands of the perianth-segments 2, orbicular. 



1. Z. glaberrimus. 

 Plants bulbous ; gland only 1, sometimes faint or a mere spot. 



Gland distinctly obcordate; perianth-segments 8-10 mm. long. 2. Z. elegans. 

 Gland not obcordate ; perianth-segments 4-8 mm. long. 



Gland with a poorly defined or irregular margin ; perianth free from the ovary ; 

 western species. 



Leaves 6-16 mm. wide ; flowers mostly perfect. 3. Z. Niittallii. 



Leaves 4-6 mm. wide ; flowers polygamous. 4. Z. venenosus. 



Gland a mere yellow spot ; perianth adnate to the ovary ; eastern coast species. 



5. Z. leimanthoides. 



1. Zygadenus glaberrimus Michx. Large-flowered Zygadenus. (I. F. 

 f. 976.) Slightly glaucous; stem stout, 6-12 dm. tall. Leaves 6-12 mm. wide, 

 channeled, often 3 dm. long or more, the upper appressed, passing into the bracts 

 of the panicle ; panicle 1.5-3 dm. long, its branches ascending ; pedicels longer 

 than the bractlets ; flowers white, mostly perfect, 2.5-3.5 cm. broad; perianth-seg- 

 ments lanceolate or oblong-lanceolate, narrowed into a short claw ; styles subulate; 

 capsule shorter than the perianth. In swamps, Va. to Fla. July-Sept. 



2. Zygadenus elegans Pursh. Glaucous Zygadenus. (I. F. f. 977.) 

 Very glaucous ; bulb about 2.5 cm. long. Stem slender, 1.5-9 dm. tall ; leaves 

 4-14 mm. wide, keeled, the lower 1-3 dm. long ; bracts green or purplish ; inflo- 

 rescence sometimes 3 dm. long, open, its branches ascending; flowers greenish, 1.6- 

 2 cm. broad ; perianth-segments oval or obovate, obtuse, united below and adnate 

 to the base of the ovary ; capsule oblong, exceeding the perianth. In moist places,. 

 N. B. to Alaska, Vt, N. Y., Mo., and in the Rocky Mts. to N. Mex. June-Aug. 



3. Zygadenus Nuttallii (A. Gray) S. Wats. Nuttall's Zygadenus. (I. F. 

 f. 978.) Light green, scarcely glaucous ; stem 3-6 dm. high. Leaves 6-16 mm. 

 wide, shorter than the stem, strongly conduplicate; inflorescence racemose or panic- 

 ulate ; bracts shorter than the slender pedicels ; flowers mostly perfect, about 1 2 

 mm. broad ; perianth-segments oval or ovate, obtuse, free from the ovary, thin, 

 short-clawed ; capsule 8-12 mm. long. On prairies, Kans. and Colo, to Tex. 

 May-June. 



4. Zygadenus venenosus S. Wats. Poisonous Zygadenus. (I. F. f. 979.) 

 Pale green ; stem slender, 1.5-6 dm. tall, from a small coated bulb. Leaves con- 

 duplicate, roughish, 4-6 mm. wide, shorter than the stem ; inflorescence a raceme. 

 5-10 cm. long in flower, elongating in fruit, the pedicels longer than the bracts ; 

 flowers yellow or yellowish, polygamous, about 8 mm. wide ; perianth -segments 

 ovate or elliptic, short-clawed, free from the ovary, bearing a roundish gland with 

 an irregular margin ; fruiting pedicels erect ; capsule longer than the perianth. 

 S. Dak. and Mont, to Br. Col., Neb., Utah and Cal. May-June. 



5. Zygadenus leimanthoides (A. Gray) S. Wats. Pine-barren Zygade- 

 nus. (I. F. f. 980.) Stem slender, 3-12 dm. high, from a fibrous-coated bulb. 

 Leaves 4-8 mm. wide, green on both sides, blunt, or the upper acuminate; panicle 

 1-3 dm. long, its branches densely many-flowered, spreading or ascending; bract- 

 lets much shorter than the pedicels; flowers mostly perfect, white or greenish, about 

 8 mm. broad; perianth-segments oblong, obtuse, not clawed, adnate to the base of 

 the ovary, bearing a basal yellowish spot; capsule ovoid, much longer than the 

 perianth. In swamps or wet soil, S. L. I. to Ga. July-Aug. 



q. MELANTHIUM L. 



Tall leafy herbs, perennial by thick rootstocks, the stem, at least its upper part, 

 pubescent. Leaves oval, oblanceolate or linear. Flowers greenish, white orj 

 cream-colored, darker in withering, monoecious or polygamous, in a large terminal 

 panicle. Perianth of 6 separate persistent clawed segments, free from the ovary. 

 Stamens shorter than the segments and adnate to them; anthers cordate or reniform, 

 their sacs confluent. Ovary ovoid; styles 3, subulate. Capsule 3-lobed, 3-celled, the 

 cavities several-seeded. Seeds flat and winged, several in each cavity. [Greek, signi- 

 fying black flower.] The genus comprises the following species and one in Florida : 





