78 TRIANDRIA. MONOGYNIA. 



terior valve tricUiitatc or 3 awned, interior bi- 

 dentate. *ycutrcd corolla of 1 valve, with 3 ex- 

 serted awns. Seed naked, oblong, compressed, 

 with a longitudinal furrow. 



Spikes alternately disposed In a long or short raceme, 

 definite or numerous:; glumes by pairs, opposite, appear- 

 ing- pectinate; rachis acuminated beyond the spikes; valves 

 of the calix narrow, riefid. mucronate, of a bluish purple, 

 persistent. Nerves of the corolla mucronate or awned; 

 awns short, long-est in the neutral flower, 2 of the 3 near- 

 ly unconnected, arising- from the base of the neutral valve. 

 Anthers o, linear, fulvous. Styles 2, filiform, siigma plu- 

 mose. (A genus nearly allied to Sesleria.) 



S p E ci ES. 1. A- aphidoides, ( Chloris airtipetidula, IVI ic H. 

 Cynoaunis senmdiis? Pursh, Appendix, p. 728.) Spikes 

 short, numerous, (30 or 40) reflected downwards, alter- 

 nately disposed upon a long raceme, each containing 

 from 4 to 10 glumes, disposed by pairs upon a compress- 

 ed rachis, mucronately terminated; outer valve of the ca- 

 lix oblong lanceolate, rigid, shortly mucronate, without 

 pubescence, generally with a single cartilaginous nerve, 

 which is a little liispid, (seen through a lens); inner valve 

 adhering to the rachis, nearly the length of the outer, 

 very narrow, l-nerved, resembling a bristle. Corolla 

 smooth, outer valve of the hermaphrodite S-toothcd, in- 

 ner 2. Neutral flower of one folded valve, 3-awned, the 

 central awn exserted beyond the calix, the 2 others in- 

 cluded, arising nearly from the base of the valve, (im- 

 properly considered, and described by Michaux, as the 

 rudiments of 2 other flowers.) — This grass begins to ap- 

 pear in the Western parts of Pennsylvania, and continues 

 to be met with tlirough Ohio, Illinois, Louisiana, and up 

 the Missouri, probably to its sources. Like the Seslena 

 aerulea, it appears to be confined to calcareous soil. 



2. Ji. *oligostachywr.. Spikes 2 or 3, nearly terminal, 

 many floweied; calix and corolla pilose; outer valve of the 

 corolla distinctly 3-awned, the 2 lateral awns shorter, aris- 

 ing near the middle of the valve; neutral valve 3-awned. 

 On tl)e plains of the Missouri with the above. Common. 

 Culm round, filiform, nearly naked, or with a single 

 kat", o to 12 inches high, smooth and erect. Leaves very 

 short, smooth, and subulate, stipule and base of the spikes 

 shortly bearded. Spikes 1, 2, or 3, about an inch long, 

 usually curved backwards, unilateral, compressed, and 

 pectinate, the second spikes bibracteate, rachis Semite- 

 lete. Glumes in a double row, opposite; each 2-floweredi 



