CJRAMIXK.-E. (CKASS FAMILY.) 545 



5. S. SertftilUlS. Smooth; culms rcnj slender, flatfish (8' -15' high), 



few-leaved; leaves very slender, channelled; panicle soon much exsertcd, the dif- 

 fuse capillary brandies scattered ; glumes ovate, obtuse, about half the length 

 of the paleae. I ? ( Agr. & Vilfa serotina, Ton: V. tcnera, Trin. Poa ? uni- 

 flora, Mithl. P. modesta, Titckerm.) Sandy wet places, E. New England to 

 New Jersey and Michigan. Sept. A very delicate grass; the spikelets, &c. 

 smaller than in the last. 



7. AGROSTIS, L. BENT-GRASS. 



Spikelets 1 -flowered, in an open panicle. Glumes somewhat equal, or the 

 lower rather longer, usually longer than the paleae, pointless. Paleaj very thin, 

 pointless, naked ; the lower 3- 5-nerved, and frequently awned on the back, the 

 upper often minute or wanting. Stamens chiefly 3. Grain (caryopsis) free. 

 Culms usually tufted, slender. (Name from oypos, a field, the place of 

 growth.. ) 



1. TRICHODIUM, Michx. Upper palea abortive, minute, or none. 



1. A. data, Trin. (TALLER THIN-GRASS.) Culms firm or stout (2 -3 

 high) ; leaves flat (l"-2" wide); upper ligules elongated (2" -3" long) ; spike- 

 lets crowded on the branches of the spreading panicle above the middle (l^'Mong); 

 lower palea awnless, slightly shorter than the rather unequal glumes ; the upper 

 wanting. 1J. (A. Sehwcinitzii, Trin. 3* A. altissima, Tuekerm., excl. var. laxa. 

 Trich. elatum, Pursh.) Swamps, New Jersey and southward. October. 



2. A. pereimaiJS, Tuekerm. (THIN-GRASS.) Culms slender, erect from. 

 a decumbent base (l-2 high); leaves flat (the upper 4' -6' long, l"-2" 

 wide) ; panicle at length diffusely spreading, pale green, the branches short, divided 

 and flower-bearing from or below the middle ; lower palea awnless (rarely short- 

 awned), shorter than the unequal glumes ; the upper minute or obsolete, y. 

 (Cornucopias perennans, Walt. Trich. perennans, Ell. T. decumbens, Michx. 

 T. scabrum, MM., not Agr. scabra, Willd. Agr. anomala, Willd.) Damp 

 shaded places. July, Aug. Spikelets, &c. as in No. 3, into which it appears 

 to vary. 



3. A. scabra, Willd. (HAIR-GRASS.) Culms very slender, erect ( 1 - 2 

 high) ; leaves short and narrow, the lower soon involute (the upper 1' - 3' long, 

 less than 1" wide) ; panicle very hose and divergent, purplish, the long capillary 

 branches flower-bearing at and near the apex ; lower palea awnless or occasionally 

 short-awned on the back, shorter than the rather unequal very acute glumes ; tho 

 upper minute or obsolete. 1J. (2) ? (A. laxiflora, Richard. A. Michauxii, Trin. 

 partly. Trich. laxiflorum, Michx. T. montanum, Torr.) Exsiccated places, 

 common. June, July. Remarkable for the long and divergent capillary 

 branches of the extremely loose panicle ; these are whorled, rough with very 

 minute bristles (under a lens), as also the keel of the glumes. Spikelets 1' 

 long. A variety? from about the White Mountains, &c. (var. raontana, 

 Tuekerm.), has a more or less exserted awn, thus differing from the T. monta- 

 num, Torr. (A. oreophila, Trin.), which is a dwarfed form, growing in tuft.- in 

 hollows of rocks, &c. 



