156 NORTH AMERICAN FLORA [VoLUME 21 
Panicles loose and open; bracts and sepals 
copiously villous; sepals of the staminate 
flowers 2 mm. long or less. 24, I. Calea. 
Stems herbaceous throughout, or suffrutescent at the base, never truly 
fruticose. 
Leaf-blades linear, 2 mm. wide or less. 25. I. inaguensis. 
Leaf-blades lanceolate or narrowly oblong to broadly ovate or orbicu- 
lar, 0.4~-7 cm. wide. 
Leaf-blades green, never retuse at the apex. 
Pubescence of the inflorescence of lustrous, bright amber- 
colored hairs; bracts dentate near the base. 26, I. acicularis. 
Pubescence of whitish hairs, or wanting; bracts entire. 
Leaf-blades obtuse, narrowly oblong to oblong-lanceolate. 27. I. flavescens. 
Leaf-blades, at least the upper ones, acute to attenuate, 
¢ lanceolate to broadly ovate. 
Sepals of the pistillate flowers faintly 1-nerved, acute, 
equaling or usually shorter than the utricle; plants 
perennial, with rootstocks, 28. I. rhizomatosa. 
Sepals of the pistillate flowers 3-nerved, usually obtuse, 
longer than the utricle; annuals or perennials. 
Flowers small, 0.5-0.75 mm. long, the spikelets 1.75 
mim. thick or less; upper leaves narrowly lance- 
olate, long-attenuate; plants suffrutescent below. 29. I. frutescens. 
Flowers larger, 1 mm. long or more, the spikelets 
—4 mm. thick; upper leaves ovate or broadly 
ovate, acute or acuminate; plants herbaceous. 
Annual; sepals of the pistillate flowers obtuse or 
acutish; lower leaves similar to the upper ones, 
acuminate, inconspicuously veined, thin. 30. I. Celosia. 
Perennial; sepals of the pistillate flowers acute 
or acuminate; lower leaves much broader 
than the upper ones, obtuse or acutish, con- 
spicuously nerved with coarse whitish veins, 
thick and succulent. 31. I. heterophylla, 
Leaf-blades variegated with red or yellow, suborbicular, retuse at 
. 32, I. Herbstii. 
the apex. 
1. Iresine jaliscana Uline & Bray, Bot. Gaz. 21: 351. 1896. 
Ascending or decumbent perennial, suffruticose below, sparsely branched, the branches 
slender, striate, green, glabrous, or very sparsely short-villous when young; petioles slender, 
5-8 mm. long; leaf-blades ovate or rhombic-ovate, 2.5-6 cm. long, 1-1.7 cm. wide, acute or 
acuminate at the apex, obtuse or rounded and slightly decurrent at the base, thin, glabrous; 
flowers polygamo-dioecious, loosely paniculate, the panicle pyramidal, nearly naked, the 
very slender branches ascending or spreading; spikelets elongate, sessile or pedunculate, the 
rachis lanate; bracts and bractlets ovate, about as long as the sepals, acuminate, mucronate, 
glabrous, scarious, stramineous; sepals oblong, hyaline, 1.5 mm, long, short-lanate at the base; 
pistillate flowers with 5 short imperfect stamens, the staminodia minute; style short, the 
stigmas elongate, slender; utricle turbinate. 
TYPE LocALIry: Near Guadalajara, Jalisco. ; 
DISTRIBUTION: Known only from the type locality. 
2. Iresine arbuscula Uline & Bray, Bot. Gaz. 21: 350. 1896. 
Tree, 4.5-6 meters high, the branches terete, smooth, glabrous; petioles 2.5-4 cm. long; 
leaf-blades elliptic or oblong-elliptic, 14-21 cm. long, 5.5-7 cm. wide, acute or acuminate at 
both ends, rather thick, deep-green, glabrous, prominently veined, the veins ascending; 
flowers polygamo-dioecious, loosely paniculate, the panicle as broad as long, the branches 
divaricate, puberulent or glabrate, subtended by narrow scarious bracts; spikelets mostly 
sessile, the rachis lanate; bracts and bractlets ovate-orbicular, rounded at the apex, scarious, 
stramineous, glabrous; sepals of the staminate flowers oblong-oval, 1.5 mm. long, obtuse, 
enervate, very sparsely lanate at the base, pale-stramineous; staminodia minute; stigma elon- 
gate; utricle ovoid. 
Type LocaLity: Volcan de Tecuamburro, Santa Rosa, Guatemala, at 2000 meters. 
DIstRIBUTION: Southern Guatemala, 
3. Iresine tomentella Standley, Contr. U. S. Nat. Herb. 18: 97. 1916. 
Shrub; branches slender, sparsely whitish-tomentose when young, glabrate in age; petioles 
0.8-1.5 em. long, tomentulose when young; leaf-blades oblong-elliptic, elliptic, or oblanceolate- 
