402 



ORDER 155. GRAMINEJS. 



8 P. alpiiia L. Culms erect, 012'; Ive. broad-linear, 12' by 23"; panicle 



ovoid-oblong, loose, with rather large (3") ovate epikclet? ; flowers about 5(49), 

 ovate, it Isle Royal, L. Superior (Porter), C. W., and North. 



9 I*, compressa L. Blue G. Plant bluish green ; culm compressed, decumbent at 



base, rigid. 12 18' ; pan. contracted, 3' by 1', or less ; epikelets glomerate, ovato 

 oblong; fls. 3 7, 1" long. l[ Pasture?, etc. : common. May, June. 



10 P. sylvestris Gr. Culm compressed, erect, 1 2f; Ivs. linear, soft; pan. oblong 

 pyramidal, thin ; branches llexuotis, the middle longest; ppkl. oval, 1|" ; fid. about 

 3. lance-oblong, 1". obtuse, it Woods', meadows, N. Y. to Va., and W. 



1 1 P cresia Sin. (P. nemoralis Torr. P. alsodes Gr. P. Gtiadini K.) Culm com- 

 pressed, 18 30', sheathed to near the top; pan, targe (012' long), loose, roughish; 

 spkl. lance-ovate, 22^"; fls. 2 or 3, lance-linear, acute, as long as the very acute 

 glumes (li 1J") ; pales obscurely veined. K Woods, N. II. to Penn., and Wis. 



12 P. serotiua Ehrh. Foul Meadow. False fied-top. Culms erect, weak, 2 3f; 

 Ivs. rjirrow, flat, long ; ligules elongated, torn ; pan. large, open, capillary ; 8pkl. 2- 

 or 3-flwd., H 2" long, often tawny; gls. and fls, acute, narrow. 2J Wet, N. July. 



13 P. trivialis L. Hough Meadow G. Culms rough! eh backward, 2030'; lv. 

 rough-edged, the lower elongated ; ligules long, pointed ; pan. dense, lance-shaped, 

 35', epkl. subsessile, 2-3-flwd., fls.. oblong, acute, strongly 5-veined. oc N. Jn., Jl. 



14 P. pratensis L. Spear G. June G. Smooth; culm 1 2f, terete; ligules 

 short, truncate; pan. open, egg-shaped, 3 10'; spkl. ovate, eubsessile, 2", abont 

 4-flowered; fls. ovate, acute, close. 2f Abundant and valuable. April, May. 



46. BRYZOPYRUM, Link. Spikelets oo.flow- 

 c-red, compressed, crowded in a spikelike panicle. 

 Glumes unequal. Pales awnless, sub-coriaceous, 

 not carinate, obsoletely many-veined. U Leaves 

 mostly rolled, smooth and rigid. Fls. dioecious. 



B. tspicatiini Hook, (a) Culm rigid, erect, 1020', 

 branched at base, beset with many bayonet shaped Ivs., 

 13', the highest exceeding the short, spikelike panicle 

 (a); spkl. (b, c) 7-9-flwd. (d, pistillate flower, e, a sta- 

 men.) Salt marshes, Conn, to Car. July. 



47. GLYCERIA, Br. MANNA G. Spikelets 

 OC-flwd., teretish or turgid, rachis jointed. Glume 



subequal, pointless. Pales awnlcss, webless, her- 

 baceous, the lower mostly 7-veincd, rounded on the back, not carinate. 

 Grain free. U Smooth grasses in Avet places, with 

 i-reeping rhi/omes and simple panicles. Sheatlis 

 mostly listular (not split). 



g Salt marsh grasses. Lower pale 5-veined. 



Stigmas sessile, simply plumed Nos. 1, 2 



$ In fresh swamps, etc. Lower pale 7- veined. 



Stigmas doubly phimous. ..(a) 

 a Spikelets linear-lanceolate, in a very sim- 

 ple panicle Noe. 3, 4 



a Spikelets linear-oblong, in compound, 



spreading panicles Nos. 5, 6 



a Spikelets ovate, short, turgid... (b) 



b In slender appressed panicles Xos. 7, 8 



b In an open, recurved panicle Nos. Q, 10 



