Part 1, 1909] POACEAE 79 
scales 4, the outermost one very broad, almost boat-shaped, enclosing the inner ones and 
the narrow rachis; second and third scales empty, the latter and the fourth scale, which 
encloses the flower, hyaline; style very long, filiform. Grain free, included between the 
stony scale and the rachis-internode. 
Type species, Euchlaena mexicana Schrad. 
1. Euchlaena mexicana Schrad. Ind. Sem. Hort. Goetting. 
1832. —Linnaea 8: Litt. 25. 1833. 
Reana Giovanninii Brign. Ind. Sem. Hort. Mutin. 1849.— Ann. Sci, Nat. III. 12: 365. 1849. 
Reana luxurians Durieu, Bull. Soc. Acclim. II. 9: 581. 1872. 
Euchlaena Bourgaet Fourn. Bull. Soc. Bot. Belg. 15: 468. 1876. 
Euchiaena Giovanninit Fourn. Bull. Soc. Bot. Belg. 15: 468. 1876. 
Euchlaena luxurians Durieu & Asch. Bull. Soc. Linn. Paris 1: 107. 1877. 
A variable grass, perhaps representing more than one species. Stems up to 5 m. tall, 
slender or stout; leaf-blades up to 1 m. long and 8 cm. wide, usually elongate, lanceolate, 
acuminate; staminate racemes up to 1.5 dm. long, the spikelets about 8 mm. long ; pistil- 
late spikelets concealed in the leaf-sheaths, the internodes with oblique ends, hence when 
short appearing triangular. 
TYPE LOCALITY: Mexico. 
DISTRIBUTION: Mexico and Guatemala, and extensively cultivated in warm and tropical 
regions. 
ILLUSTRATIONS: Bot. Mag. p/. 6414; Bull. U. S. Dep. Agr. Agrost. 20: 7. 1; Vasey, Agr. 
Grasses U. S. ed. 2. pl. 22; Bull. U. S. Dep. Agr. Agrost. 15: /. 72, Beal, Grasses N. Am. 2: 
J. 1; Sull. Tenn. Exp. Sta. 5: f. 32-34. 
2. ZEAL. Sp. Pl. 971. 1753. 
Mays (Tourn.) Gaertn. Fruct.1: 6. 1788. 
Tall monoecious grasses with broad ample leaf-blades, the staminate spikelets borne in 
terminal panicles, the pistillate sessile in many rows on a spongy thick rachis in the axils 
of the leaves: Staminate spikelets in pairs, 2-flowered, unequally pedicellate or nearly 
sessile ; scales 4, the outer 2 larger, membranous, the inner 2 hyaline and bearing flowers ; 
stamens 3. Pistillate spikelets closely sessile, densely crowded in longitudinal rows upon 
a thick spongy unarticulated rachis, the entire inflorescence completely enclosed in large 
herbaceous sheathing bracts; scales 4, membranous, usually hyaline, commonly short and 
broad, rarely large, the fourth bearing a flower ; styles very long, filiform, shortly 2-toothed 
at the apex. Grain naked, excepting at the base, or rarely enclosed in the enlarged scales. 
Type species, Zea Mays L. 
1. Zea Mays Ll. Sp. Pl. 971. 1753. 
Mays Zea Gaertn. Fruct.1: 6. 1788. 
? Zea canina S. Wats. Proc. Am. Acad. 26: 160. 1891. 
Stems up to 3 m. tall; leaf-blades up to 1 m. long and 1 dm. wide, usually recurved 
and drooping at the apex; staminate inflorescence up to 2 dm. long or more, its branches 
spreading and drooping; pistillate inflorescence varying much in form and size, the grains 
or kernels also variable in form and color. 
TYPE LOCALITY: America. 
DISTRIBUTION: Widely cultivated in tropical and warm temperate regions all over the world, 
and often escaping from cultivation. 
ILLUSTRATIONS: Schkuhr, Handb. p/. 283; Burger, Abhandl. Mais #7. 7-4, T. Nees, Pl. Off. 
Suppl. 4: p/. 1,2; E. Duchesne, Traité Mais p/. 7-7; Bonafous, Hist. Mais p/. 1-12, Dict. Sci. 
Nat. Monocot. p/. 23, 24, Descourt. Fl. Ant. £/.544 ; Lam. Tab. Encyc. ss 749 » Ann. Mus. Paris 17: 
pl. 6; iar U. 8. Dep. Agr. Agrost. 20: f. 2; Beal, Grasses N. Am. 2: 7.2; Bull. Tenn. Exp. 
Sta.5 5, 
3. TRIPSACUM L. Syst. Nat. ed. 10. 1261. 1759. 
Digitaria Heist.; Adans. Fam. Pl. 2: 550. 1763. 
Tall perennial grasses, with stout rootstocks, usually broad flat leaf-blades, and the 
spikelets in spikes or the upper portion racemose. Rachis articulated, the lower portion 
bearing pistillate, the upper staminate, spikelets. Pistillate spikelets 1-flowered, in excava- 
tions in the rachis, the outer scales very hard, thick and shining, concealing the more deli- 
