Genus 33. 



GRASS FAMILY. 



181 



8. Aristida longiseta Steud. Long-awned 

 Aristida. Fig. 430. 



A. longiseta Steud. Syn. Gram. 420. 1855. 



Culms tufted, 8'-i6' tall, simple; blades 1-4' long, 

 involute; panicle 4-8' long, its branches usually 

 ascending, bearing generally 1 spikelet, or in the 

 longer branches sometimes 2 spikelets; spikelets 

 io"-i2l" long, the 2 outer scales i-nerved, the first 

 one about J as long as the second, the flowering scale 

 6"-8" long, occasionally a little shorter, from a little 

 over J to I as long as- the second scale, the awns 

 ascending, the central one 2i'-4$' long, the lateral 

 ones equalling it or a little shorter. 



In dry sandy soil, Montana and Washington to Ne- 

 braska, Texas and Mexico. July, Aug. 



g. Aristida oligantha Michx. Few-flowered Aristida. Fig. 431. 



Aristida oligantha Michx. Fl. Bor. Am. 1: 41. 1803. 



Glabrous, culms i°-2° tall, erect, slender, dichot- 

 omously branched, smooth or roughish. Sheaths ex- 

 ceeding the internodes, loose; ligule very short, minutely 

 ciliate; blades i'-6' long, i"-i" wide, smooth, the larger- 

 ones attenuate into a long slender point ; spikelets few, 

 borne in a lax spike-like raceme or panicle; first scale 

 S-nerved, occasionally 7-nerved at base, acuminate or 

 short-awned, equalling or somewhat shorter than the 

 second, which bears an awn 2"-^" long; third scale 

 shorter than the first, awns divergent or spreading, the 

 middle one ii'-2i' long, the lateral somewhat shorter. 



Dry soil, New Jersey to Nebraska, and Texas. Aug.— 

 Sept. Ant-rice. 



10. Aristida gracilis Ell. Slender Triple-awned 

 Grass. Fig. 432. 



Aristida gracilis Ell. Bot. S. C. & Ga. 1 : 142. 181 7. 



Aristida gracilis var. depauperata A. Gray, Man. Ed. 5, 

 618. 1867. 



Glabrous' and smooth throughout, culms 6'-2° tall, 

 erect, simple or branched. Sheaths shorter than the 

 internodes; ligule very short; blades i'-4' long, 1" wide 

 or less, flat, or involute when dry ; panicle spike-like, 

 3-7' long, slender; spikelets about 3" long; outer scales 

 equal, or the lower somewhat shorter, awn-pointed; 

 third scale about equalling the second, generally mottled, 

 middle awn horizontal, the terminal straight portion 

 3"-7" in length, the lateral awns i"-3" long, erect. 



Dry soil, New Hampshire to Missouri, south to Florida 

 and Texas. Aug.-Sept. 



