xeidack^. clkis family.) 459 



Order 123. IRIDAcE^. (Iris Family.) 



Herbs, with equUant %ranked leaves, and regidar or irregular perfect floio- 

 ers ; the divisions of the 6-eleft petaUike perianth convolute in the hud in 2 

 sets, the tube coherent with the 3-ceUed ovary, and 3 distinct or monadelphous 

 stamens with extrorse anthers. — Flowers from a 2-leaved spathe, usually 

 showy and ephemeral. Style single : stigmas 3, alternate with the cells of 

 the ovary. Pod 3-celled, locolicidal, many-seeded. Seeds anatropous: 

 embryo straight in fleshy albumen. Eootstocks, tubers, &c. mostly acrid. 

 — A rather small family, here represented by only two genera. 



1* IRIS, L. FLOWER-DB-LuClii. 



Perianth 6-cleft; the 3 outer diyisions spreading or roflexod; the 3 inner 

 smaller and erect. Stamens distinct, placed before the outer diyisions of the 

 perianth, and under the 3 petal-like stigmas. Pod 3 - 6-ajigled. Seeds de- 

 pressed-flattened. — Perennials with creeping and often tuberous rootstocks, 

 sword-shaped or grassy leaves, and large showy flowers. Cipw, the rainbow 

 deified, anciently applied to this genus on account of the bright and varied 

 colors of the blossoms.) 



* Stems leafy (l°-3° high), often branching: rootstocks thick: flowers crestiess, the 



inner divisions {peteds) much smaller than the outer. 



1. I. versicolor, L. (Laboer Blue Flag.) Stem stout, angled on 

 one side ; leaves sword-shaped (|' wide) ; ovaiy obtusely triangular with the sides 

 flat; pod oblong, turgid, with rounded angles. — Wet places; common. May, 

 June. — Plowers blue, variegated with green, yellow and white at the base, and 

 veined with purple. 



2. I. Tirginica, L. (Slender Blue Flag.) Stem very slender, 

 terete ; leaves narrowly linear (i' wide) ; ovary 3-angled, and each side deeply 

 2-grooved ; pod triangular, acute at both ends. (I. prismatica, Pursh. I. gra- 

 cilis, Bigd.) — Marshes, Maine to Virginia, and southward, near the coast. 

 June. — Flower much smaller than in the last. 



* * Low, almost stemless, 1 -3 flowered: divisions of the light blue-purple perianth 

 nearly equal : rootstocks slender, and here and there tuberous-thickened, a'eeping and 

 tufted. 



3. I. verna, L. (Dwarf Ibis.) Leaves linear, grass-like, ratlier glau- 

 cous, the thread-like tube of the perianth about the length of the divisions, which 

 are all beardless and crestiess ; pod triangular. — Wooded hill-sides, Virginia, 

 Kentucky, and southward. April. 



4. I> CriStata, Ait. (Crested Dwarf Iris.) Leaves lanceolate (3'- 

 5' long when grown) ; those of the spathe ovate-lanceolate, shorter than the 

 thread-like tube of the perianth, which is 2' long and considerably exceedi the divis- 

 ions ; the outer ones crested, but beardless ; pod sharply triangular. — Mountains 

 of Virginia, Kentucky, and southward. May. 



5. I. lacustris, Nutt. (Lake Dwarf Ikis.) Tube of the perianth rather 

 shorter than the divisions (yellowish, J'- 1' long), diluted upwards, not exceeding 



