GEAMINEAE. 43 



First scale about equalling the second. 



Perennials; culms from long rootstocks. 6. S. Torreyanus. 



Annuals ; roots fibrous, no rootstocks. ' 7. S, serotimis. 



1. Sporobolus asper (Miehx.) Kunth. M, p. 104. In dry soil. Autumn. 



Lancaster — (P.). 



2. Sporobolus longifolius (Torr.) Wood. M. p. 105. In dry soil. Late 



summer. 

 BifcA's— Nockaniixon (P.). Montgomery— (P.). Lancaster— {P.), 

 Northampton— (P.) . Dauphin— (P.). 



3. Sporobolus vaginaeflorus (Torr.) Wood. M. p. 105. In dry soil. 



Summer. 



4. Sporobolus Indicus (L.) R. Br. M. p. 106. Ballast. Summer. 



Philadelphia — Navy Yard. 



CaiHr?en— Petty 's Island, I. Burlc (Fu.). 



5. Sporobolus heterolepis A. Gray. M. p. 106. Dry soil. Summer. 



Lancaster — Pleasant Grove (Ca.), New Texas (P.). 



6. Sporobolus Torreyanus (R & S.) Nash. M. p. 107. Pine barrens. 



Autumn. 



7. Sporobolus serotinus (Torr.) A. Gray. M. p. 107. Sandy wet places 



in pine barrens. Autumn. 



28. POLYPOGON Desf. 



1. PoLYPOGON MoNSPELiENSis (L.) Desf. Beard-grass. M. p. 108. Bal- 

 last. Summer. 

 PJiiladelphia-GiTard Point, I. Burk (He.). Bucks — (P.). 



29. CINNA L. Wood Reed Grass. 



Panicle narrow at maturity, its filiform branches erect or drooping ; spikelets 

 4-5 mm. long; first scale much shorter than the second. 



1. C. arundinacea. 



Panicle open, its capillary branches flexuous and drooping; spikelets 3 mm, 

 long; first scale about equalling the second. 2. C. latifolia. 



1. CiNNA ARUNDINACEA L. M. p. 108. Moist woods and shaded swamps. 



Summer. 

 Fennsylvania — General. ' 



Cajndert— Camden (C). Gloucester— M.ick\eion (C), 



2. CiNNA LATIFOLIA (Trev.) Griseb. M. p. 108. Damp woods. Late sum- 



mer. 

 Lancaster — Pequea, A. A. Seller (He.). 



30. AGROSTIS L. 



Palet conspicuous, at least one-third as long as the scale. 1. A. alba. 

 Palet inconspicuous, minute or wanting. 



Third scale awned. 2. A. canina. 



Third scale not awned, or very rarely bearing a short awn. 



Culms weak, usually decumbent and often prostrate at base; leaves 



lax; spikelets 1.5 mm. long. 3. A. perennans. 



Culms and leaves erect. 



