6b TRIANDRIA. DIGYNIA. 



28. reptans. Ambiguous species. — 59. melicoides.\ 30. 

 Airoides.i 



Of the 78 species of this g-enus in Persoon, tliere are 

 28 in Europe, the rest in North ^. merica, Barbai y, India, 

 the tropical islands of Anier'ca, a ^ew species at the Cape 

 of Good Hope, and some in the isle of New Zealand. As 

 yet there are only 2 species described as growing in the 

 whole continent of South America. • 



A genus of the utmost importance in agriculture. 



97. BRIZA. L, (Quaking-grass.) 



Calix 2-valved, many-fl ^wercd. Spikelets 



grostis, in which the larger valve of the calix is also 3-nerved, 

 similar to the coi-olla. 



Hab. Collected in the neighbourhood of Philadelphia, by Dr. 

 W. Barton, professor of Botany. 



f Panicle small, composed of a few simple racemes; calix 

 unequal, obi use, sliorter than 'he corolla, 2 (»r 3-flowered; flow- 

 ers oblong-obovate, obtuse, nerved, connected to the ruchis by 

 a i.omentose villus; culm long and slender; leaf short, smooth, 

 attennakd 



Jtira nielicoiiles, Mich. A. trifora? El. 



\ Culm 4 or 5 feet high, erect, leaves with very long sheathes, 

 short and acute; panicle erect, aitenna'ed; bi-anclics srmiverti- 

 cillate, few and capillary; spikelets «)blong, obtuse, nearly ses- 

 sile, or ui)on short peduncles, 4 to 6-fiovvered: caliv very un- 

 equal, shorter than the corolla; fl.Avevs distinct, somewna't cy- 

 lindric, obtuse, shining, purplish, scariose, and ofien lacera.e at 

 the point, obsoletely 5-nerved, inner valve scabious on the 

 margin. 



Hab In depressed situations around the .Mandan village, on 

 the Missouri, v-v. 



Scarcely distinct from Poa distans, except in habit; being 4 

 or 5 feet high, with leaves sometimes embracing the cuIiti for 

 8 inches, scabrous on the margin, acute, arKl scarcelv more 

 than an inch, or an inch and a half long. The panicle is also 

 attenuated, the branches capillary, loose, but erect, never re- 

 fracted. In most of which characters it differs from the /*. 

 dista7is, and docs not at all agree wth Curtls*s figure. !t is 

 another of those ambiguous grasses, which, (like the P.disians 

 and ,^ira aquatica now considered the same plant.) combines 

 the characters of 2 genera; it has the artificial character of Poa, 

 but it is in fact an Aim, althouKh producing 4, 5, and 6 flowers 

 in a spikelet. It is probably an important meadow-grass, like 

 the Aira aquatica. 



