146 



GKAMINEAE (GRASS FAMILY) 



§ 1. CHONDROSIUM (Desv.) Gray. Spikes 1-4, nsnally cm-ved, o/ 25 ot 



more densely crowded pectinate spikelets. 



1. B. oligostachya (Nutt.) Torr. Culms slender, erect, from a short root- 

 stock, leafy at the base, 1.5-5 dm. high ; sheaths and blades glabrous, the latter 



about 2 mm. wide, flat or becoming convolute ; spikes 1-3, 

 2-5 cm. long ; spikelets 5-f') mm. long ; glumes" narrow, the 

 first about ^ as long as the second, which is sjmrsely papiUose- 

 pilose on the keel ; fertile lemma pilose, S-cleft, the divisions 

 awned ; sterile lemma consisting of 2 truncate lobes and 3 

 divergent equal awns with a tuft of long hairs at base, second 

 rudiment obtuse, awnless. — Prairies, Wis. and N. Dak. to 

 Tex. ; casual eastw. (Mex.) July-Sept. Fig. 137. 



2. B. hirsuta Lag. Culms tufted, erect, 2-5 dm. high, 

 leafy at the base ; sheaths smooth ; blades about 3 mm. wide, 

 flat, sparsely papillose-hairy, especially on 

 the margins; spikes 1-4, 1.5-5 cm. long; \\UL\\>?y 



the rhachis (f the spike produced into a VwM^ 



prominent point beyond the nppermost spikelets; spikelets 

 abcHit 5 mm. long ; lirst glume setaceotis, the second equaling 

 the floret, conspicuously tvherculate-hirsute on the back; fer- 

 tile lemma pubescent, 3-cleft, the divisions awn-pointed ; 

 sterile Horet of % obtuse lobes and 3 equal awns margined 138. B. hirsuta. 

 l>elow, no tuft of hairs at the base. — Sandy plains. Wis. to Spikelet with glumes 

 Mo., and southwestw. to Mex. July-Sept. Fig. 13«. detache(! x8. 



§ 2. ATHEROPOGON (Muhl.) Gray. Spikes 15 or more, oj 12 or fewer ascend- 

 ing spikelets. 



137. B. oligostachya. 



S pikelet with glumes 



detached x3. 



3. B. curtip§ndula (Michx.) Torr. Culms erect from short running root- 

 stocks, 3-10 dm. high ; sheaths pubescent toward the summit ; blades 1-3 dm. 



long, 3-5 mm. wide, flat or involute and setaceous toward 

 the end, scabrous above, sometimes pubescent beneath ; spikes 

 numerous, 8-1 (^ mm. long, spreading or retlexed. in a long 

 n;ostly 1-sided raceme, the rhachis bifid at the extended apex; 

 spikelets 7-10 mm. long; first glume less than | the length 

 of the second which is very scabrous on the thickened keel, 

 exceeding the floret ; lemma scabrous, ending in 3 short 

 slender awns ; teeth of palpa 

 2 acute lobes and 3 straight 

 shorter than the middle awn. 



hills and plains, Ct. to Minn., s. to Tex. and Mex 

 Sept. — The sterile lemma variable, rarely reduced to a single awn. Fig 



139. B. curtipendula. 

 Part of inflorescence 



ari state ; sterile lemma with 

 aw))s, the lateral ones much 

 {B. racemosa Lair.) — Dry 



July- 

 139. 



55. CTENIUM Panzer. Toothache Grass 



Spikelets with 1 perfect flower and 2-5 sterile lemmas, 

 crowded and sessile, pectinate in 1-sided spikes ; glumes very 

 unequal, first minute, second nearly as long as the spikelet, 

 bearing a stout horizontally divergent dorsal awn from abotit 

 the middle; first and second lemmas empty or sometimes 

 with a hyaline palea, awned below the apex, awn erect or 

 ascending ; third lemma similar, containing a perfect flower ; 

 fourth awnle.ss, staminate or empty ; a liflh rudiuumtary 

 lemma often present. — Rather tall perennials with solitary 

 terminal more or less cttrved spikes. (Name from Krevlov, 

 a smnJl comb, from the pectinate appearance of the spike.) 

 Camim'i.osis Desv. 



1. C. aromaticum (Walt.) Hitchc. Culms 1-1.5 m. liigh, 

 erect, from sf^aly rootstocks. old sheatlis persistent at the 

 base; blades long, flat or involute, stiff; spike 0.5-1.5 dm. 



140. C. aromaticum. 

 Inflorescence x %. 

 Spikelet X 2. 

 Same. with glumes 

 detached x 2. 



