16 
16. A. attenuata Vasey. Bot. Gaz. x1. 337. Culms slender, erect, attenuated, 2 to 
3 feet long, smooth; radical leaves narrowly linear, 2 to 4 inches long, those of the 
culm about 3, distant; sheaths shorter than the internodes, smooth ; ligule conspic- 
uous, 2 to 3 lines long; blade 2 to 4 inches long, narrow, acuminate; panicle oblong 
or pyramidal, 3 to 4 inches long (remarkably short for the length of the culm); lower 
rays in threes or fives, somewhat unequal, 1 to 2 inches long, erect-spreading, capil- 
lary, few-flowered; pedicels mostly longer than the spikelets; empty glumes equal, 
about 14 lines long, oblong-lanceolate, acute, scabrous on the keel; flowering glume 
nearly as long, not awned; palet wanting.—In swampy ground, Mount Hood, Ore- 
gon (Thomas Howell). 
17. A. perennans Tuck. (Trichodium perennans Ell.; T. decumbens Michx.) Culms 
more or less slender, often decumbent at base, 1 to 24 feet high, simple or branching 
below; leaves flat, 1 to 3 lines wide, 2 to 6 inches long; panicle 4 to 8 inches long, 
diffuse, the rays 2 to 4 inches long, variable as to number, the lower often numerous 
and verticillate, branched below the middle; spikelets at the extremity of rather 
long pedicels; empty glumes rather unequal, acute or acuminate, hispid on the keel; 
floral glume one-fourth shorter, not awned; palet wanting.—Widely dispersed; flow- 
ers in autumn. 
Var. ZSTIVALIS. More slender, less tall; panicle longer, often occupying one-half 
to two-thirds of the culm, the rays more capillary and shorter, flowering much earlier 
(June to August).—Illinois, Tennessee, and southward. 
18, A. elata Trin. (Gray’s Manual, 6th ed., p. 648.) Culms firm or stout, 2 to 3 feet ° 
high; leaves flat, 110 2 lines wide; upper ligule elongated (2 to 3 lines long); panicle 
open, 5 to 9 inches long, lower branches in fives or more, unequal, the longer 3 to 4 
inches long, flowering above the middle; spikelets somewhat crowded near the ex- 
tremities of the branchlets, 14 lines long, acute; floral glume about as long as the 
empty ones, acutely 2-toothed at the apex; palet wanting.—Sandy swamps, New 
Jersey and southward, 
19. A. Nove-Anglie. (4. scabra var. montana Tuck.) Culms perennial, rather 
firm, somewhat geniculate below, 1 to 2 feet high, smooth; leaves of radical tufts, 4 
to 6 inches long; those of the culm 3 to 4 inches long, 1 to 2 lines wide, flat, soft, 
smooth; ligule 1 line long, obtuse; upper sheaths very long (3 to 5 inches); panicle 
pyramidal or oblong, purplish, 4 to 5 inches long; lower rays mostly in fives, some- 
what unequal, the longer ones 2 to 3 inches long, the upper ones in twos or threes and 
gradually shorter, rather few-flowered near the ends; empty glumes oblong-lanceo- 
late, acute; floral glume nearly as long, awned near the apex.—Mountains of New 
England. 
20, A. HowelliiScribn. Culms about 2 feet high, weak, geniculate and decumbent 
below, 3- to 5-leaved; leaves flat, 6 to 10 inches long, 3 lines wide, the upper ones 
equaling the panicle, rather scabrous; ligule 1 to 2 lines long, decurrent; sheaths 
about equal to the internodes, smooth; panicle 8 to 10 inches long, flexuous, pale or 
whitish, very open and thin, the lower rays in threes to fives, the upper in pairs, the 
longer 3 to 4 inches long, capillary, sparingly branched below the middle, distant ; 
spikelets 14 lines long, on rather long pedicels; empty glumes rather unequal, acute, 
slightly scabrous on the keel, otherwise smooth; floral glume equaling the shorter 
empty one, narrow, the 4 lateral nerves projecting as setaceous teeth, the stout awn 
near the base bent and about 2Jines long, a few minute hairs at the base; palet 
wanting.—Near Hood River, Oregon (No. 198, Howell). 
F. Panicle short and dense; rays crowded. 
21. A. Rosse n. sp. Apparently cespitose ; culms about 6 inches high, smooth; 
Jeaves mostly near the base, Linch long or less, erect, or appressed ; sheaths rather loose, 
striate, the upper reaching to the middle of the culm; panicle oblong, 1 to 14 inches 
long, the comparatively long rays verticillate, erect, and appressed, 4 to # inch long, 
subdivided above, and the few spikelets crowded at the extremities; empty glumes 
