166 



POACEAE 



35. ASPRIS Adans. 



Spikelets 2-flowered, disarticulating above the glumes, the rachilla not prolonged ; glumes 

 about equal, acute, membranaceous or subscarious ; lemmas firm, rounded on the back, 

 tapering into 2 slender teeth, bearing on the back below the middle a slender geniculate 

 twisted usually exscrted awn, this rarely wanting in the lower floret or reduced; callus 

 bearing a very short tuft of hairs. Delicate annuals with open or contracted panicles of 

 small spikelets. [A Greek name for a grass.] 



Species 5, warmer parts of Europe. Type species, Aira praecox L. 

 Panicle dense, spikelike. 1- A. praecox. 



Panicle open. . ■ . 



Lower floret awnless or nearly so. 2. A. capxllaris. 



Lower floret with awn as long as that from the upper floret. 3. A. cayyophyllea. 



1. Aspris praecox (L. ) Nash. 

 Little Hair-grass. Fig. 374. 



Aira praecox L. Sp. PI. 65. 1753. 



Aspris praecox Nash in Britt. & Brown, Illustr. Fl. ed. 2. 1: 215. 

 1913. 



.■\nnual; culm.s tufted, up to 20 cm. tall, usually 

 erect; blades setaceous; panicle narrow, den^e. 1-3 cm. 

 long; spikelets yellowish, shining, 3.5-4 mm. long; 

 lemmas bidentate at apex, bearing a geniculate awn 

 2-4 mm. long from below the middle, the awn of the 

 lower floret shorter than that of the upper. 



.Sandy open ground, Washington and Oregon (Seaside); also 

 in the Atlantic States. June-July. Type locality, European. 



2. Aspris capillaris (Host) Hitchc. 



Diffuse Hair-grass. 



Fig. 375. 



Aira capillaris Host, Icon. Gram. Austr. 4: 20. pi. 35. 1809. 

 Aspris capillaris Hitchc. U. S. Dept. Agr. Bull. 772: 116. 1920. 



Similar to A. caryofhyllea ; panicle more diffuse; 

 spikelets scattered at the ends of the branches, 2.5 inm. 

 long; lemma of lower floret awnless or with a minute 

 awn just below the apex; the teeth short; lemma of 

 upper floret bearing a geniculate awn 3 mm. long from 

 below the middle, the tee'th setaceous. 



Open ground, sparingly introduced in California (Redwood 

 Creek, Kenyan). May. Type locality, European. 





3. Aspris caryophyllea (L.) Nash. 

 Silvery Hair-grass. Fig. 376. 



.4ira caryophyllea L. Sp. PI. 66. 1753. 



Aspris caryophyllea Nash in Britt. & Brown, Illustr. Fl. ed. 2. 1: 

 214. 1913." 



Annual ; culms solitary or few, slender, erect. 10-30 

 cm. tall; blades short, setaceous; panicle open, the 

 silvery shining spikelets 3 mm. long, clustered toward 

 the ends of the spreading capillary branches ; lemma 

 of both florets with a geniculate awn 4 mm. long from 

 below the middle, the teeth of the apex setaceous. 



Open dry ground, Vancouver Island to southern California; 

 also in the eastern States. May-June. Type locality, European. 



