56 Mr. Woods on the Genera of European Grasses. 



so, and we sometimes observe a small mucro on the outer palea of Sclerochloa ; 

 the others are constantly unarmed. 



1 . Glumes nearly or quite as long as the spicula. 



42. Aira. Glumes 2-flowered, without any rudiment. Awn, if any, dorsal, 

 geniculate and twisted. The palese in some species harden on the seed, 

 but without adhering to it. 



43. Deschampsia. Glumes 2-flowered, with usually the not club-like rudi- 

 ment of a third. Outer palea truncate, with a straight awn, from near 

 the base ; surrounded with soft hairs. 



53. Melica. Glumes nearly equal, larger than the paleae, 1- or 2-flowered, 

 with the additional stalked, club-like rudiment of 1 or 2 more. Paleae 

 unarmed, membranous, hardening on the seed. 



.^0. Danthonia. Glumes 2 or more flowered. Outer palea smooth and coria- 

 ceous below, membranous and nerved above, emarginate, with an inter- 

 mediate broad tooth, sometimes terminated with a geniculate and twisted 

 awn. 



52, Schismus. Glumes many-flowered, much larger than the palea, membra- 

 nous, ribbed, with a scariose margin. Outer palea similar, subtruncate. 

 (According to Palisot de Beauvois, there is a terminal seta.) 



5 1 . Kceleria. Glumes and outer palea herbaceo-scariose ; the latter entire, 

 acute, or with a terminal or subapicular, not geniculate seta. Spiculee 

 ovate. 



45. Trisetum. Glumes and outer paleae keeled, membrano-scariose, without 

 prominent nerves. The latter ending in two teeth, with a slender dorsal 

 awn, which in most species is geniculate. Seed without furrow or crest. 



46. Avena. Glumes herbaceous or membranous, with a scariose margin. Outer 



palea firmer than the glume, ribbed, ending in two points, with an inter- 

 mediate geniculate and twisted dorsal awn, which however is sometimes 

 wanting. Seed furrowed and crested. 



2. Glumes decidedly falling short of the spicula. 



58. Poa. Glumes nearly equal. Outer palea compressed, keeled, membranous, 

 with a scariose margin, entire, somewhat acute, unarmed. Panicle equal. , 



