MISSOURI MUHLENBERGIAS 21 



Glumes one-fourth to one-half as long as the spikelets, ovate - 

 acuminate; lemmas with awns 1-2 mm. long; rootstocks much 



stouter. • 2. MUHLENBERGIA CURTISETOSA. 



B. Stenocladium section. 



I. Spikelets i.5-2mm. long; lemmas awnless; infranodes' 

 minutely scabrous just below the glabrous nodes; glumes two- 

 thirds to three-fourths as long as the scabrous lemmas, ovate to 

 broadly lanceolate, cuspidate. 3. Muhlenbergia sobolifera. 



1. Spikelets 2.5-4mm. long; lemmas awned or rarely awnless; 

 glumes lanceolate or broadly lanceolate. 2. 



2. Spikelets 2. 5 -3 mm. long; infranodes glabrous; nodes 

 glabrous; culms low, much-branched; panicles numerous, upper 

 usually short-exserted; awns 3-4mm. long. 



4. Muhlenbergia brachyphylla. 

 2. Spikelets 3 -4mm. long; infranodes retrorsely pubescent; 

 nodes pubescent; culms usually tall, little branched; panicles 

 usually few, usually long-exserted ; glumes very broad, ovate- 

 lanceolate, cuspidate, scabrous, clasping, one-half to two thirds 

 as long as the scabrous slender lemmas; lemmas usually with long 

 awns, rarely awn-pointed or awnless; awns 5-iomm. long. 



5. Muhlenbergia tenuiflora. 



C. AcROXis section. 



I. Glumes much exceeding the lemmas, generally twice as long, 

 about 5mm. long, awned-acuminate ; lemmas acuminate-attenuate. 



6. Muhlenbergia racemosa. 



1. Glumes about as long as the lemmas, or slightly longer, 

 or mostly a little shorter, less than 5m.m. long, glabrous or rarely 

 slightly scabrous. 2. 



2. Panicles ovoid or subpyramidal, or sometimes linear, num- 

 erous, short-exserted, or partially included in the upper sheaths 

 not dense nor glomerate -flowered. 3. 



2. Panicles oblong or cylindrical, or sometimes linear, more 

 or less glomerate, or sometimes loosely flowered. 5. 



3. Panicles numerous, rather long, more or less open; lemmas 

 long-awned, 7. Muhlenbergia commutata. 



The term infranode is here employed to designate that portion of the 

 culm just below the node, corresponding to the upper part of the internode. 



