128 



GRAMINEAE (GRASS FAMILY) 



Var. paliistris Scribn. Similar to the species ; cwlms reclining or ascending, 

 very slender or almost filiform ; leaves 2-4 cm. long, 2-3 mm. wide ; panicles 

 5-10 cm, long, very slender, more loosely flowered; spilcelets (excluding the 

 awn) 2.5 mm. long, usually purple; glumes acute, unequal, 

 the first about \, the second about \ the length of the hidentate 

 awned lemma; awn flexuous, 4-6 mm. long. (M. palustris 

 Scribn.) — Swampy ground, D. C. and 111. Sept., Oct. 



§ 2. TRICH6CHL0A (Beauv.) Trin. Panicle very loose and 

 open, the long branches and pedicels capillary; leaves narrow, 

 often convolute-bristle-form. 



8. M. capill^ris (Lam.) Trin. (Haik Grass.) Caespitose, 

 erect, with simple rigid culms, 6-10 dm. high ; sheaths overlap- 

 ping; blades 1-3 dm. long, involute, rigid; panicle about \ the , 

 entire height of the plant, its spreading -Mpillary branches loosely 

 flowered; spikelets purple, 4 mm. long (excluding the awn) ; 

 glumes subequal, acute, or the second aristate-pointed, about \ as 

 long as the lemma which bears a delicate awn 5-20 mm. long. — 

 91. M. capiilaris. Dry sandy or gravelly soil, Mass. to Fla. , west to Mo. and Tex. 

 Spikelet x8. Fia. 91. 



27. BRACHY^LYTRUM Beauv. 



Spikelets 1-flowered, in a few-flowered narrow panicle ; glumes minute, 

 unequal ; floret vfith a short callus, the rbachilla prolonged 

 behind the palea into a slender naked bristle ; lemma firm, 

 narrow, 5-nerved, terminating in a long straight awn ; palea 

 firm, nearly as long as the lemma ; grain oblong, inclosed in 

 the lemma and palea. —Perennials, with simple culms from 

 short knotty rootstocks. (Name composed of ^pax^s, short, 

 and eXvTpof, husk, from the minute glumes.) 



1. B. erictum (Schreb.) Beauv. Culms erect, 5-10 dm. 

 high ; sheaths sparsely retrorse-hispid ; blades 8-15 cm. long, 

 1-1.8 mm. wide, lanceolate, very scabrous, pilose on the 

 nerves beneath ; panicle narrow, 1-2 dm. long ; spikelets 1 cm. 

 long (excluding the awns), on capillary pedicels ; first glume 

 often obsolete, second sometimes aristate ; floret scabrous. 

 {B. aristatum Beauv.) — Rocky woods, Nfd. to Minn., and 92. B. erectuni. 

 SOUthw. July, Aug. Fig. 92. Spikelets x 1%. 



93. H. scboenoldes. 

 Inflorescence x %, 

 Spikelets x 8. 



28. HELE6CHL0A Host 



Spikelets 1-flowered, flattened, in dense oblong-ovoid spike- 

 like panicles ; glumes awnless, shorter than the 1-nerved lemma 

 which subtends a palea of nearly equal length. — Low caespi- 

 tose branching annuals, the numerous spike-like panicles 

 partly included in the inflated sheaths. (Name from IXos, 

 a meadow, and x^^'^i grass.) 



1. H. schoenoIdes (L.) Host. Usually almost prostrate; 

 leaves rather rigid, tapering to a sharp point ; spike 1.6-4 cm. 

 long. — Waste places, N. Y. to Del. and e. Pa. ; also Chicago, 

 111. {Bebb). (Adv. from Eu.) Fig. 93. 



29. phl£;0ii l. 



Spikelets 1-flpwered, flattened, in dense cylindrical spike-like panicles; 

 glumes equal, ciliate on the keels, and abruptly awn-pointed, longer than the 



