GRAMINEAE. 95 



long, straight and erect. In dry soil, Mo. and Kans. to the Ind. Terr. ; also in Va. 

 Sept.-Oct. 



3. Aristida basiramea Engelm. FORKED ARISTIDA. (I. F. f. 299.) Culms 

 tufted, rather slender, 2-6 dm. tall, branching. Leaves 3-15 cm. long, 1.5 mm. 

 wid_- or less; panicle 3-9 cm. long, the branches erect; spikelets 10-15 mm - l n g 

 the first scale much shorter than the second; the flowering scale 7-11 mm. long, 

 considerably shorter than the second scale; the lateral awns more or less spread- 

 ing, usually a little spiral at the base, one-half to two-thirds as long as the central 

 awn, which is strongly spiral at the base. In dry places, Minn, to Neb., south to 

 111. and Kans. 



4. Aristida ramoslssima Engelm. BRANCHED ARISTIDA. (I. F. f. 300.) 

 Culms 1.5-6 dm. tall, branched. Leaves 3.5-7.5 cm. long, 2 mm. wide or less, 

 flat, smooth beneath, scabrous above; spikelets few, borne in loose spikes, 5-10 cm. 

 in length; first scale awn-pointed; second scale 1.6-2 cm. in length, exceeding the 

 first, terminated with an awn 2-6 mm. long; third scale as long as the second; 

 middle awn about 2.5 cm. long, forming a hook, the lateral awns erect. In dry 

 soil, 111. to Ky. and Mo. July-Sept. 



5. Aristida fasciculata Torr. BUSHY ARISTIDA. (I. F. f. 306.) Culms 3-6 

 dm. tall, branched. Leaves 5-15 cm. long, 2 mm. wide or less, flat; panicle 7.5- 

 17.5 cm. long, at first strict, the branches finally more or less spreading; first scale of 

 spikelet I -nerved, shorter than the second scale; third scale equalling or longer 

 than the second; awns divergent, the middle one 8-16 mm. long, the lateral ones 

 shorter. Dry soil, Kans. to Cal., south to Mex. Aug.-Sept. (Arislida dispersa 

 Trin. and Rupr.) 



6. Aristida Fendleriana Steud. FENDLER'S ARISTIDA. (I. F. f. 304.) Culms 

 densely tufted, 1.5-2.5 dm. tall, erect, rigid, simple. Sheaths smooth, confined to 

 the base of the culm ; leaves involute, at least when dry, often curved, 0.5 mm. in 

 diameter; panicle 7-10 cm. long, strict, its branches short and appressed and 

 usually bearing a single spikelet; spikelets 1.21.5 cm. long, the flowering scale 

 9-12 mm. long, the central awn 2-3.5 cm - l n g> tne lateral ones a little shorter. 

 In dry sandy soil, Black Hills to Neb. and Utah, south to Tex. and N. Mex. 

 (Aristida pur pur ea Nutt. in part.) 



7. Aristida longiseta Steud. LONG-AWNED ARISTIDA. Culms tufted, 2-4 

 dm. tall, simple. Leaves 310 cm. long, involute, at least when dry; panicle 12 

 dm. long, its branches usually bearing but a single spikelet; spikelets --2.5 cm. 

 long, the flowering scale 1.2-1.6 cm. long, from a little over one-half to two-thirds 

 as long as the second scale, the central awn 6-1 1 cm. long, the lateral ones equal- 

 ling it or a little shorter. In dry sandy soil, Neb. to Mont, and Wash., south 

 to Tex. and Mex. (Aristida purpurea Nutt. in part. ) 



8. Aristida oligantha Michx. FEW-FLOWERED ARISTIDA. (I. F. f. 303.) 

 Culms 3-6 dm. tall, dichotomously branched. Leaves 2.5-15 cm. long, 1-2 mm. 

 wide, smooth; spikelets few, in a lax spike-like raceme or panicle; first scale 5 - 

 nerved, occasionally 7-nerved at base, equalling or somewhat shorter than the 

 second, which bears an awn 4-8 mm. long; third scale shorter than the first, awns 

 divergent or spreading, the middle one 3.7-6.2 cm. long, the lateral somewhat 

 shorter. Dry soil, N. J. to Neb., south to La. and Tex. Aug.-Sept. 



9. Aristida stri^ta Michx. ERECT ARISTIDA. (I. F. f. 305.) Culms o 12 

 dm. tall. Leaves involute-filiform, the basal 3 dm, or more in length, those of the 

 culm 2-3 dm. long, or the upper shorter; panicle spike-like, strict, or the top some- 

 times nodding, 1.5-6 dm. long; outer scales of the spikelet awn-pointed, the first 

 I -nerved, shorter than the second; third scale equalling the first or a little shorter; 

 middle awn 1-2 cm. long, horizontal when old, the lateral ones shorter, erect o\ 

 divergent. Dry soil, Va. (icrording to S. Watson), south to Fla. July-Sept. 



10. Aristida gracilis Lll. SLENDER ARISTIDA. (I. F. f. 298.) Culms 

 1,5-6 dm. tall. Leaves 2.5-10 cm. long, 2 mm. wide or less, flat, or involute when 

 dry; panicle spike-like, 7.5-17.5 cm. long, slender; spikelets about 6 mm. long; 

 outer scales about equal; third scale about equalling the second, generally mottled, 

 middle awn horizontal, the lateral awns 26 mm. long, erect. Dry soil, N. H. and 

 Mass, to 111. and Neb., south to Fla. and Tex. Aug.-Sept. * 



11. Aristida purpura=cens Poir. PURPLISH ARISTIDA. (I. F. f. 301.) Culms 

 3-7.5 dm. tall. Leaves :-2 dm. long, about 2 mm. wide, flat, or becoming invo- 



