520 MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



culms and sheaths, and firm flat or folded blades abruptly rounded at the tip. 



Section 1. Eustachys. 

 Lemmas distinctly awned (awn very short in C. cucullata), pale or fuscous. 



Section 2. Euchloris. 



Section 1. Eustachys 



Spikes numerous, usually more than 10 1. C. glauca. 



Spikes usually not more than 6. 



Spikelets 2 mm. long; lemmas dark 2. C. petraea. 



Spikelets 3 mm. long; lemmas pale to golden brown until maturity. 



Spikes 2, sometimes 1 or 3 3. C. floridana. 



Spikes 4 to 6 4. C. neglecta. 



Section 2. Euchloris 



Rudiment narrow, oblong, acute, often inconspicuous. (Second rudiment truncate in C. 

 gay ana). 



Plant producing long, stout stolons 5. C. gayana. 



Plant not stoloniferous (occasionally with short stolons in C. andropogonoides). 



Fertile lemma about 2.5 mm. long; plants mostly less than 50 cm. tall; spikes mostly 



less than 10 cm. long 7. C. andropogonoides. 



Fertile lemma 4 to 7 mm. long; plants 40 to 100 cm. or more tall; spikes mostly more 

 than 10 cm. long. 

 Blades folded, abruptly acute or rounded; spikes whorled, naked at base. 



8. C. texensis. 

 Blades flat, long-acuminate; spikes racemose on a short axis, solitary or in small 



fascicles 6. C. chloride a. 



Rudiment truncate-broadened at apex, usually conspicuous (rather narrow in C. virgata). 

 Lemma conspiculusly ciliate-villous, the spikes feathery. 



Plants annual. Lemma long-ciliate on the lateral nerves near apex 9. C. virgata. 



Plants perennial. 



Spikes flexuous, nodding, mostly 10 to 15 cm. long; hairs much exceeding the spike- 

 lets 10. C. POLYDACTYLA. 



Spikes straight or subflexuous, 5 to 7 cm. long; hairs about equaling the spikelets. 



11. C. CILIATA. 

 Lemma minutely ciliate on the nerves or glabrous, the spikes not feathery. 



Awn of fertile lemma usually 3 to 8 mm. long; spikes mostly 7 to 12 cm. long, the spike- 

 lets not closely crowded 12. C. verticillata. 



Awn of fertile lemma usually less than 3 mm. long ; spikes usually less than 6 cm. long, 

 the spikelets crowded. 

 Awns about 1 mm. long; rudiment prominent, inflated, broadly triangular-truncate, 



about 1.5 mm. wide as folded at summit 15. C. cucullata. 



Awns 2 to 3 mm. long; rudiment not inflated, not more than 1 mm. wide as folded at 

 summit. 

 Rudiment oblong-cuneate, about 0.6 mm. wide as folded at summit. 



13. C. SUBDOLICHOSTACHYA. 



Rudiment triangular-truncate, about 1 mm. wide as folded at summit. 



14. C. latisquamea. 



Section 1. Eustachys (Desv.) Reichenb. , ' - ., ,*_ , , 7 



much as 1 cm. wide, the tip abruptly 



Lemmas firm, brown to blackish, rounded; spikes several to many (as 

 awnless or mucronate only; many as 20), ascending, 7 to 12 cm. 

 glumes scabrous, the second mu- long; spikelets about 2 mm. long; 

 cronate from a notched or trun- lemma glabrous or scaberulous on the 

 cate summit. Perennials. nerves. % (Eustachys glauca 

 1. Chloris glauca (Chapm.) Wood. Chapm.) — Brackish marshes, wet 

 (Fig. 756.) Glaucous; culms erect, prairies, and swamps, North Carolina 

 compressed, stout, 70 to 150 cm. tall; (Wilmington), Georgia (Baker Coun- 

 basal sheaths several, broad, com- ty), and Florida, 

 pressed, keeled, overlapping and equi- 2. Chloris petraea Swartz. (Fig. 

 tant, those of the succeeding 1 or 2 757.) Often glaucous, sometimes pur- 

 distant nodes similar, 2 to 4 leaves plish; culms slender, 50 to 100 cm. 

 aggregate; blades flat or folded, as tall, more or less decumbent and root- 



