HITCHCOCK—MEXICAN GRASSES. 377 
Glumes strongly unequal, the lower not more 
than one-third as long as the second........ 3. F. myuros. 
Glumes but slightly unequal. 
Main panicle branches divergent............ 2. F. pacifica. 
Main panicle branches appressed. 
Lemmas smooth or scabrous.........--.-- 1. F. octoflora. 
Lemmas hirtellous............-.-------- la. F. octoflora hirtella. 
Plants perennial. 
Plants loosely tufted, the slender culms decumbent at 
base; blades narrow, folded or involute, smooth 
or nearly 80. ..........2-0-.- 22 eee eee eee ees 5. F. rubra glaucodea. 
Plants densely tufted. 
Blades flat, coarse; culms 1 meter high or more... 11. F. amplissima. 
Blades folded or involute, or sometimes with flat 
blades intermixed. 
Blades smooth. 
Plants not in cushions; culms usually 
over 40 cm. high, the open pani- 
cles much exceeding the leaves; 
spikelets 8 to 10 mm. long, the 
glumes about 4 mm. long.......... 10. F. willdenoviana. 
Plants in dense cushions; culms 10 to 20 
em. high, the short panicles not 
much exceeding the leaves; spike- 
lets few, pendulous, 10 to 14 mm. 
long, the glumes 10 to13mm.long. 13. F. livida. 
Blades scabrous. 
Plants tall and coarse; blades scattered ; 
lemmas distinctly awned. 
First glume 4 to 5 mm., second 5 to 6 
mm. long; lemma scaberulous.. 8. F. tolucensis. 
First glume 7 to 8 mm., second 8 to 9 
mm. long, both of them narrow 
and long-acuminate; lemma 
strongly scabrous........------ 12. F. mirabilis. 
Plants lower and more delicate; blades 
mostly basal; lemmas awnless or 
mucronate (or short-awned in no. 7). 
First glume 5 mm. long; blades of in- 
novations very slender, 0.5 mm. 
wide, 30 cm. or more long...... 9. F. roset. 
First glume 3 to 4 mm. long. 
Lower panicle branches short, 
appressed; blades of inno- 
vations mostly less than 10 
cm. long; lemmas often 
short-awned........------ 7. F. hephaestophila. 
Lower panicle branches spread- 
ing, naked below; lemmas 
not awned. 
Blades all involute, capil- 
we eee scenes eee eee 6a. F. ovina callosa. 
Blades partly flat, these 2 to 
5 mm. wide.........-. 6. F. ovina elliptica. 
