io6 



POACEAE 



Panicle 2.5-4 

 cm. long, its 

 axis minute- 

 ly pubescent. 

 Panicle 5-7.5 

 cm. long; axis 

 hirsute. 

 Pubescence not spreading. 

 Ligule short; culms 

 villous puberu- 

 lent. 

 Culms erect, rigid. 

 Culms weak, fas- 

 ciculately de- 

 cumbent. 

 Ligule 2 mm. long or 

 more; culmswith 

 long, stiff, ap- 

 pressed hairs. 

 Blades glabrous on 

 the upper 

 surface. 

 Spikelets 1.2- 

 1.3 mm. long. 

 Spikelets 11 o t 

 over 1 mm. 

 long. 

 Blades pubescent 

 on the upper 

 surface. 

 Spikelets 2 mm. long or more. 

 Spikelets pointed. 

 Spikelets not pointed. 

 Ligule 2-5 mm. long. 

 Pubescence spread- 

 ing. 

 Pubescence not 

 spreading. 

 Pubescence 

 sparse and 

 stiff; upper 

 i n t ernodes 

 shortened. 

 Pubescence 

 silky; upper 

 i n ternodes 

 not short- 

 ened. 

 Ligule short. 



Panicle 4-5.5 cm. 

 long, oblong, 

 dense. 



45. P. meridionale. 

 44. P. implicatum. 



50. P. columbianum. 



51. P. tsugetorum. 



37. P. leucothrix. 



38. P. Wrightianiim. 



45. P. meridionale. 



41. P. languidum. 



42. P. villosissimum. 



40. P. scoparioides. 



43. P. pseudopubescens. 



48. P. Addisoni. 



