190 GRAMINEAE. 
7. Eragrostis sessilispica Buckley. Prairie Eragrostis. (Fig. 434.) 
Eragrostis sessilispica Buckley, Proc. Acad. Phila. 1862: 
97. 1862. 
Diplachne rigida Vasey, Grasses S. W., Part 2. fl. gr. 
1891. 
Culms 8’-3%4° tall, erect, simple, smooth and gla- 
brous. Sheaths short, crowded at the base of the 
culm, smooth, pilose at the summit; ligule a ring of 
short hairs; leaves 2/-6’ long, 3’/-114’’ wide, rough 
above, glabrous or sparingly pilose beneath; panicle 
8/-16’ in length, the branches stout, rigid, widely 
diverging; spikelets scattered, closely sessile, ap- 
pressed, 5-12-flowered, 4’’-7’/ long, empty scales 
about equal in length, acute; flowering scales very 
acute, about 2’’ long, the lateral nerves very prominent. 
Prairies, Kansas to Texas. Aug.—Sept. 
8. Eragrostis curtipedicellata Buckley. 
Short-stalked Eragrostis. (Fig. 435.) 
Eragrostis curtipedicellata Buckley, Proc. Acad. Phila. 
1802: 97. 1862. 
Culms 6/—3° tall, erect, rigid, simple, smooth and 
glabrous. Sheaths overlapping, smooth, pilose at the 
summit; ligule a ring of short hairs; leaves 2’-8/ long, 
1//-2// wide, smooth beneath, scabrous aboye; panicle 
4/-12/ in length, the branches widely spreading, 1%4/— 
414’ long; spikelets 5-12-flowered, 114’’-3’’ long, on 
pedicels of less than their own length; scales acute, the 
empty ones somewhat unequal, the flowering ones 
about 7%’/ long, scabrous on the midnerve, their lateral 
nerves prominent. 
3 V 
Prairies, Kansas to Texas. Aug.-Sept. 
g. Eragrostis pectinacea (Michx.) Steud. Purple Eragrostis. (Fig. 436.) 
Poa pectinacea Michx. Fl. Bor. Am. 1:69. 1803. 
Eragrostis pectinacea Steud. Syn. Pl. Gram. 272. 1855. 
Eragrostis pectinacea var. spectabilis A. Gray, Man. 
Ed. 5, 632. 1867. 
Culms 1°-2%° tall, erect or ascending, rigid, 
simple, smooth and glabrous. Sheaths overlapping, 
smooth, glabrous or villous, the upper one often 
enclosing the base of the panicle; ligule a ring of 
hairs; leaves 5/-12’ long, 2’’-4’’ wide, smooth be- 
neath, scabrous above and sparingly villous at the 
base; panicle 6’-24’ in length, purple or purplish, 
the branches 3/—10’ long, strongly bearded in the 
axils, widely spreading or the lower often reflexed; 
spikelets 5-15-flowered, 1'4’’-4’’ long, on pedicels 
of at least their own length; scales acute, the empty 
ones about equal, the flowering ones about 7%’” 
long, their lateral nerves very prominent. 
In dry soil, Massachusetts to Illinois and South 
Dakota, south to Florida and Texas. Aug.—Sept. 
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