906 POACE^. 



not webbed at the base, ovate, acute, 4 mm. long, the upper third 

 soarious; palea linear, 3.7 mm. long, scabrid on the keels. 



Mexico, Pringle 1437, Palmer 1316 ; New Mexico, Tracy. 



43. P. Oronttiana Vasey, West. Am. Scientist in Aug. 1887. 



An erect perennial, about 60 cm. high. Leaves of the culm 3 in 

 number, sheaths smooth; ligule scarious, fringed, 5 mm. long; blades 

 of sterile shoots thin, flat, taper-iK)inted, 10-15 cm. long, the upper 

 blade of the culm 5-7 cm. long. Panicle purplish, 12-15 cm. 

 long, rays in fours and fives, the longest 8-9 cm. long, bearing about 

 25 spikelets on the outer half. Spikelets linear, purplish, 6-8 mm. 

 long, 3-5-flowered, scaberulous; empty glumes thin, 3-nerved and 

 green only near the base, first 3 mm. long, second 3-4 mm. long; 

 floral glume thin, 3.4-4.5 mm. long, with a trace of a tuft of huirs 

 at the base, oval, subacute, apex often erose; palea about the length 

 of its glume, linear before spreading, 2-tootheil, ciliolate on the 

 keels. Stamens 3. Anthers 2.5 mm. long. 



Lower California (northern i)art), Orcutt in 188(> foi* U. S, 

 Dept. Agricul. 



127. (257). COLPODnm Trin. Fund. Agrost. 119 (1820). Arc- 

 tophila Rupr. Beit. Pfl. Russ. Reich. 2: 62 (1845). 



Spikelets 1-2-flowered, rarely 3-flowered, rachilla arti; ulate 

 above the lower glumes and between the florets. Empty glumes 

 awnless, softly membranous or hyaline, 1-3-nervetl or destitute of 

 nerves, obtuse or rather acute, unequal; floral /^hmie with the tex- 

 ture of the empty glumes, very broad, obtuse, more or less 5-nerved, 

 the lateral ones short or almost obsolete; palea about as long as its 

 glume, hyaline, 2-nerved. Stamens 3. Styles short; distinct. 

 Grain oblong, without a groove, included, but not adherent. An- 

 nual or perennial grasses. Leaf-blades flat or almost setaceous. 

 Panicle slender, effuse, pyramidal, branches capillary. Spikelets 

 often small, sometimes colored. 



Ten species are known in Asia, Europe and North America. 

 The genus is very closely allied to Poa and by some made a section 

 of that genus. 



The spikelets are small, containing only one or two flowers, 

 thus connecting Poa with the Agrosteae. The Arctic plant pub- 



