66 TRIANDRIA. DIGYNIA. 



sion and almost pung-ent acuteness of the calix and co- 

 rolla; valves conneced at their base by a very copioi s, 

 long tomentum; panicle semiverticlllate and coarctate.) 

 4. neiyiortiHs- 5. annua. 6. alpinn? 7. cornpressa. 8. nervata. 

 9. anUimnalisy liL.f 10. aiignstifolia. 11. aquatica. \2.fui' 

 tans. 13. rigida. (These are nearly all introduced species^^ 

 or common to Europe as well as America, and of great 

 importance in agriculture.) 14. capillaris. 15. tenuis, E^. 

 16. M)\<!!ifa. 17. subverticillata. 18. crocata.^ 



§ 11. Brizoma. IJ Sp'culi erect, closely imbricated, flow- 

 er glumes often angularly 3-nerved; witliout a connecting 

 villous; valves short, ovate, obliquely pointed, (sometimes 

 producing the appearance of marginal serralures,) inner 

 valve small, seeds more or less spherical. 



f Pungens would perliaps have been a better name for this 

 early flowering vernal grass- 



Obs Root somewhat cespitose and perennial; culm partly 

 ancipital, about a foot high,. Radical leaves erect, long, and 

 narrow; leaves on the culm genei ally 2, flat, oblong, lanceolate, 

 scabrous only on tb.e margin, the lower about an inch long, the 

 upper just visible; all erect and carmate, witli a coarctate pun- 

 gent point; stipula truncate, lacerate, sometimes abruptly acu- 

 minate; sheaihcs long, but a little shorter than the nodes. Pa- 

 nicle small, semiverticillate, alternate, horizontally spreading, 

 terminating in an almost simple raceme; branches capillary, 

 mostly by twos or threes; fasciculi 3 or 4. Spicull crowded to- 

 wards ti.e extremities of the lamifications, cuneate-ovate, or 

 lanceolate, before flowering somt;what acute, 3 or 4-flowered. 

 Calix smooth, inner valve acute. Corclla ovate lanceolate, a lit- 

 tle obtuse and scariose at the point, villous at the base, obso- 

 letely 5-nerved, 3 ofthe lesser nei vesciliately pubescent below. 

 Stamina exserted, tren.ulous, bifurcate at either extremity. 

 Styles ses.sile, complicateh plumose, white. 



Hab. Around Philadelphia in rocky situations, on the banks 

 ofthe Schuylkill, Sec. Flowers in April. 



tCulm leafy, round, 18 inches or 2feet high. Leaves smooth, 

 flat, actiminatcd, 4 to 6 inches long; stipula elongated. Pani- 

 cle elfingated, stmivert cjllate, brandies appressed, numerous, 

 manv-flowered. Spjkelets in attenuated racemes, small, nearly 

 sessile, acutely ovate, generally 2-flowered, pale green, with 

 yellowish, and sometimes purplish scariose points. Calix acu- 

 minated, nearly as long as the fiosculi, obsoletely 3-nerved, and 

 carinate. Flowers oblong, rather obtuse, with a dorsal line of 

 pubescence near the base. 



JIab. In Canada. — Mr. Whitlow. Poa hydrophila? Persoon 



il Species of Poa allied to the genus Briza. 



