GRASS FAMILY. 
12. Sporobolus airoides Torr. MHair-grass Dropseed. 
Agrostis atroides Torr. Ann. Lyc. N. Y. 1: 151. 1824. 
Sporobolus airoides Torr, Pac. R. R. Rept. 7: Part 3, 21. 
1856. ; 
Culms 114°-3° tall, erect, simple, smooth and gla- 
brous. Sheaths generally shorter than the internodes, 
sometimes sparsely ciliate at the throat; ligule very 
short; leaves smooth beneath, scabrous above and 
sometimes sparingly hairy near the base, %4//-114/’ 
wide at the base, attenuate into a long slender involute 
point, the basal about one-half as long as the culm, the 
upper culm leaves 2’-5’ in length; panicle 5’-15/ long, 
usually exserted, the branches alternate or the upper 
verticillate,, at length widely spreading, the lower 3/— 
7’ long; spikelets 34’’-1’’ long, the scales acute, gla- 
brous, the outer unequal, the lower one about half as 
long as the upper; third scale equalling the second 
and the palet. 
Prairies, Nebraska to California, south to Texas and 
Arizona. Aug.—Sept. 
13. Sporobolus cryptandrus (Torr.) A. Gray. Sand Dropseed. (Fig. 353.) 
Agrostis cryptandra Torr. Ann. Lye. N. Y. 1: 151. 1824. 
Sporobolus cryptandrus A. Gray, Man. 576. 1848. 
Culms 114°-3%° tall, erect, simple or sometimes 
branched at the base, smooth and glabrous. Sheaths 
: smooth, with a dense pilose ring at the summit, the 
= lower short, crowded and overlapping, the upper 
gf much longer, generally enclosing the base of the pan- 
icle; ligule a ring of short hairs; leaves 3/—6’ long, 
1//-2/’ wide, flat, glabrous beneath, scabrous above, 
long-acuminate; panicle 6-10’ in length, the base gen- 
erally included in the upper sheath, rarely entirely 
exserted, the branches spreading or ascending, alter- 
nate, the lower 114’-3/ long; spikelets 1//-14’’ long, 
the scales acute, glabrous, the outer scabrous on the 
V/ keel, the lower one-third as long as the upper; third 
scale somewhat longer or shorter than the second. 
In sandy soil, coast of New England, along all the Great 
Lakes, west to Dakota, south in the interior to Missouri, 
Texas and Mexico. Aug.—Oct. 
14. Sporobolus heterdlepis A. Gray. Northern Dropseed. (Fig. 354.) 
Vilfa heterolepis A. Gray, Ann. Lyc. N. Y. 3: 233. 1835. 
Sporobolus heterolepis A. Gray, Man. 576. 1848. 
Culms 1°-3° tall, erect, simple, smooth and glabrous. 
Sheaths sometimes sparingly pilose at the summit, the 
lower short, loose, and overlapping, the upper much 
elongated and tight to the culm; ligule a ring of short 
hairs; leaves involute-setaceous, glabrous, the margins 
and upper part of the midrib very rough, the basal 
about three-fourths the length of the culm, occasion- 
ally equalling it, those of the culm shorter; panicle 
3/-10’ in length, its branches erect or ascending, al- 
ternate or sub-verticillate, the lower 114/-314’ long; 
spikelets 2’’-23/’’ long, the scales smooth and gla- 
brous, the outer unequal, acuminate, the lower sub- 
ulate, about half the length of the broad second one, 
often awn-pointed; third scale obtuse or acute, shorter 
than the second or occasionally equalling it. 
In dry soil, Quebec to Assiniboia, south to Pennsylvania, 
Illinois and Arkansas. Aug.-Sept. 
