GRAMINEAE 29 



30. CALAMAGROSTIS Adans. 

 Rachilla with its prolongation hairy its whole length. 

 Third scale with a much bent and exserted awn, the hairs of the callus much 



shorter than the scale. i. C. Porleri. 



Third scale with a straight or nearly straight and included awn : hairs of the 

 callus equalling the scale or but little shorter than it. 

 Panicle open, the lower branches widely spreading. 2. C. Canadensis. 

 Panicle more or less contracted. 3. C. inexpansa. 



Rachilla with its prolongation hairy only at the top. 4. C. cinnoides. 



1. Calamagrostis Porteri A. Gray. Porter's Reed-grass. (Man. 

 p. 112; I. "S.f.sjs.) In dry woods, Pa. and southern N. Y. — Pennsyl- 

 vania : Huntingdon. 



2. Calamagrostis Canadensis (Michx.) Beauv. Bi^uB- joint Grass. 

 (Man. p. 112 ; I. F. y; 373-) In swamps and wet, often sandy, soil. 

 Newf. to Alaska, N. C, N. Mex. and Calif. — Pennsylvania : Delaware ; 

 Bucks ; Northampton ; Lancaster ; Dauphin ; Carbon ; Wayne ; 

 Pike ; Monroe ; Elk ; Tioga ; Venango ; Erie. 



3. Calamagrostis inezpansa A. Gray. Bog REED-grass. (Man. p. 

 113.) Bogs and sandy banks, N.J. and western N. Y. to S. Dak. and 

 Colo. — Pennsylvania : Lycoming, in a bog near Muncy. 



4. Calamagrostis cinnoides (Muhl.) Scribn. Nuttall's REEd- 

 GRASS. (Man. p 113 ; I. F. /. 379.) In moist soil, N. H. and Mass. to 

 Ga. — Pennsylvania : Delaware ; Chester ; Bucks ; Monroe ; Lan- 

 caster ; Lebanon ; Dauphin ; Huntingdon ; Montgomery ; Schuyl- 

 kill. 



31. AMMOFHILA Host. 



1. AmmopIillaarenaria(L.)Link. Sea Sand-reed. SeaMat-weEd. 

 (Man. p. 114 ; I. V.f. 380.) In sands of the sea coast from N. B. to Va., 

 and inland along the shores of the Great Lakes. Also on the coasts of 

 northern Eu. — Pennsylvania : Erie, Presque Isle. 



32. APERA Adans. 

 1. Apera Spica-veuti (L.) Beauv. Silky Bent-grass. WindlE- 

 STRAW. (Man. p. 115; I. 'P./. 383.) In waste places and on ballast, 

 Me. to Penn. Adv. from Eu. — Pennsylvania : Philadelphia, on and 

 about ballast. 



33. HOLCUS L. 



1. Holcus lanatus L. VELVET-grass. Meadow Soet-grass. 

 (Man. p. lis; I. P- /• 3^4-) In fields and waste places, N. S. to 111., 

 N. C. and Tenn.. Also on the Pacific Coast. Nat. from En. — Pennsyl- 

 vania : Delaware ; Chester ; Bucks ; Luzerne ; Northampton ; 

 Lancaster ; Erie ; Somerset ; Jefferson ; Philadelphia ; Frank- 

 lin ; Allegheny. 



34. AIRA L. 



Panicle open : flowering scales about 2 mm, long : plants 10-25 '^^- tall. 



1. A, caryophyllea. 

 Panicle contracted : flowery scales 3 mm. long : plants 5-8 cm. tall. 



2. A.praecox. 



