Hitchcock — Tlic Grasses of Hazcaii 125 



commonly persistent ; glumes somewhat unequal, shorter than the first lemma, acute or acuminate, 

 i-nerved, or the second rarely 3-nerved; lemmas acute or acuminate, keeled or rounded on the 

 back, 3-nerved, the nerves as a rule prominent; palea 2-nerved, the keels in some species ciliate. 

 Annual or perennial grasses of various habit, the inflorescence an open or contracted panicle. 

 Plants annual ; introduced species. 



Palea prominently ciliate on the keels, the hairs about 0.3 mm. long i. E. amabilis. 



Palea not prominently ciliate on the keels. 



Lemmas glandular on the keel 2. E. cilianensis. 



Lemmas not glandular. 



Spikelets as much as 2 cm. long, denselv many-flowered 3. E. falcata. 



Spikelets less than i cm. long, loosely few to 12-flowered. 



Palea remaining on the rachilla after the fall of the lemma ; spikelets appressed 



on the branchlets 4. E. caroliniana. 



Palea and lemma deciduous from the rachilla ; spikelets on long ascending 



pedicels 5. E. abyssinica. 



Plants perennial. 



Creeping rhizomes short and stout, the culms in loose tufts 6. E. atropioides. 



Creeping rhizomes wanting, the culms in compact tufts. 



Pedicels slender, straight, stiffly ascending, mostly longer than the spikelets 



7. E. mauiensis. 



Pedicels mostly shorter than the spikelets, if longer then flexuous. 



Lower branch of the open panicle solitary, spikelets about 2 mm. wide 



8. E. brownei. 



Lower branches of panicle several in a fascicle, or the panicles narrow and spike- 

 like, obscuring the fascicles. 

 Branches of the open panicle deflexed at maturity : blades mostly less than 



4 mm. wide 9. E. deflexa. 



Branches of panicle not deflexed: panicle usually contracted, if open the blades 

 mostly more than 5 mm. wide. 

 Plants tall and stout, usually over i meter tall : panicles oblong, rather 

 open ; blades flat, usually more than 5 mm. wide, in some speci- 

 mens as much as i cm. wide 10. E. grandis. 



Plants mostly less than i meter tall, many low or slender ; panicles con- 

 tracted, or even spikelike. 

 Culms low, slender, tufted, mostly less than 30 cm. tall ; blades 

 slender, involute, mostly basal ; panicles narrow but not very 



dense, mostly 5 to 15 cm. long 11. E. moaticola. 



Culms tall, slender or stout, commonly as much as i meter tall, some 

 lower but stout. 

 Culms tall and slender ; blades slender, involute, about i mm. 

 wide when rolled; panicles slender and spikelike, 15 to 



30 cm. long- 12. E. leptophylla. 



Culms stout ; blades mostly more than 5 mm. wide, flat or becom- 

 ing involute at the tips ; panicle stout, compact or some- 

 what open, as much as 40 cm. long 13. E. variabilis. 



I. Eragrostis amabilis ( L. ) ^^■ight & .\rn.: Hook. & Arn. Bot. Beechey ^'oy. 251. 1841. 

 Poa amabilis L. Sp. PI. 68. 1753. 

 Eragrostis f'luiiiosa Link, Hort. Berol. i ;i92. 1827. 



Plants annual; culms erect or spreading and geniculate at base, slender, 10 to 30 cm. 

 tall, glabrous ; sheaths glabrous, pilose at the throat ; blades flat, lax, striate, mostly less than 

 10 cm. long, 2 to 4 mm. wide; panicle oblong, or elliptic, 5 to 15 cm. long, 3 to 6 cm. wide, 

 open, the branches ascending or spreading, pilose in the axils, slender, the pedicels finally 

 spreading, mostly as long as the spikelet or longer; spikelets 1.5 to 2 mm. long, mostly 4 to 

 6-flowered. the rachilla joints finally disarticulating: glumes broad, nearly equal, about i mm. 

 long; lemmas obtuse, about i mm. long: palea as long as the lemma, prominently ciliate, the hairs 

 straight, rather distant, about 0.3 mm. long (fig. 12). 



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