GRAMINEJE. (GRASS FAMILY.) 651 



base of the firm-membranaceous flowering glume, which bears near its base a 

 tivisted atvn of its own length. (Deyeuxia Porteri, Vase;/.) Dry woods, 

 Pulpit Rocks and vicinity, Huntingdon Co., Penn., Prof. T. C. Porter. 



8. C. Pickeringii, Gray. Culm 1 -1-J high; leaves short ; panicle py- 

 ramidal, purplish ; glumes ovate-oblong, bluntish or bluntly pointed (1^-2" 

 long) ; hairs loth of the flower and of the rudiment very short and scanty, one 

 fourth or fifth the length of the flower, none behind the obtuse flowering glume, 

 which bears between its middle and base a short stout (straight or bent, not 

 twisted) awn. (Deyeuxia Pickeringii, Vasey.) White Mts., in the alpiue 

 region of Mt. Washington, and a more luxuriant form with smaller spikelets 

 at Echo Lake, Franconia; Audover, Mass. (J. Robinson) ; Cape Breton. 



2. CALAMOVfLFA. Rudiment of second flower wanting; glumes and 

 palet rather chartaceous, compressed-keeled ; flowering glume \-nerved, en- 

 tirely awnless ; palet strongly 2-fceeled ; panicle at length open and loose. 



9. C. brevipilis, Gray. Branches of the diffuse pyramidal pauicle cap- 

 illary (purplish); empty glumes ovate, mucrouate ; the upper slightly, the 

 lower nearly one half shorter than the flowering glume and palet, which are 

 more than twice the length of the hairs and bristly-bearded along the keels. 

 ( Ammophila brevipilis, Benth.) Sandy swamps, pine-barrens of N. J. ; rare. 

 Sept. Culm 2-4 high; leaves nearly flat; spikelets 2" long. 



10. C. longifolia, Hook. Culm (1 -4 high) stout, from thick running 

 rootstocks; leaves rigid, elongated, involute above and tapering into a long 

 thread-like point ; panicle at first close, becoming open and pyramidal, the 

 branches smooth ; glumes lanceolate, the upper as long as the flower, the lower 

 shorter ; the copious hairs more than half the length of the naked fioiver. (Am- 

 mophila longifolia, Benth.) Sands, along'the upper Great Lakes, from 111. 

 and Mich, to Dak., Kan., and westward. Aug. Spikelets 2^-3" long. 



34. AMMOPHILA, Host. (PI. 15.) 



Spikelets large, in a contracted spike-like panicle, 1-flowered, with a pedicel- 

 like rudiment of a second flower (plumose above), the flower hairy-tufted at 

 base. Empty glumes scarious-chartaceous, lanceolate, compressed-keeled, 

 nearly equal ; flowering glume and palet similar, a little shorter, the glume 

 5-nerved, slightly mucronate or obscurely awned near the tip, the palet 2- 

 keeled. A coarse perennial maritime species, with running rootstocks. 

 (Name from a/^/j-os, sand, and ct>i\4w, to love.) 



1. A. arundinacea, Host. (SEA SAND-REED.) Culm stout and rigid 

 (2-3 high) from firm running rootstocks ; leaves long, soon involute ; panicle 

 contracted into a dense cylindrical spike (5 - 9' long) ; spikelets 5 - 6" long ; 

 hairs only one third of the length of the flower. (Calamagrostis arenaria, 

 Roth.) Sandy beaches, N. J. to Maine and northward, and on the Great 

 Lakes. Aug. (Eu.) 



35. ARRHENATHERUM, Beauv. OAT-GRASS. (PI. 12.) 



Spikelets open-panicled, 2-flowered, with the rudiment of a third flower ; the 

 middle flower perfect, its glume barely bristle-pointed from near the tip ; the 

 lowest flower staminate only, bearing a long bent awn below the middle of 

 the back (whence the name, from appwv, masculine, and aOyp, aivn) ; other- 

 wise as in Avena, of which it is only a peculiar modification. 



