340 American Midland Naturalist Monograph No. 7 



2. Awn scarcely exceeding the glumes; shallow water and wet 

 banks. May-July. A. aequalis Sobol. 



2. Awn bent, exserted from the spikelet 2 mm or more; ditches 

 and fields. May-June A. carolinianus Walt. 



41. Phleum L. — Timothy 



P. pratensc L. Roadsides and fields, very common; nat. from Eur. 

 June-July. 



42. Muhlenbergia Schreb. 

 1. Panicles narrow, not diffuse or spreading. 



2. First glume obsolete or nearly so, the second minute, truncate; 

 lemma long-awned. 

 3. Second glume 0.2-0.5 mm long; awn as long as or twice as 

 long as the lemma: fields and drv woods, common. Julv- 

 Oct. Nimble Will .' M. schrcben J.F.Gmel. 



3. Second glume 1.5-2 min long; awn half as long as the lemma; 



Champaign Co., Clinton in 1892. Type collected in 111. by 



J. Wolf in 1881 M. curtisctosa (Scribn.) Bush 



2. Glumes half the length ot the lemma, or longer. 



4. Plants with conspicuous scaly rhizomes. 



5. Lemma awnless or nearly so; anthers 0.5-1 mm long. 



6. Glimies lanceolate or oval, cuspidate, about half or two- 

 thirds the length of the lemma; dry or rocky woods. 



July-Oct M. sobolijera (Muhl.) Trin. 



6. Glumes subulate. 



7. Glumes equalling the lemma, or somewhat shorter, 

 awnless or short-awned. 

 8. Internodes of the stem glabrous. 



9. Panicles usually well exserted; woods in Christian, 

 Menard, Peoria, and Sangamon counties. Aug.- 

 Oct M. brachyphylla Bush 



9. Panicles shortly exserted or partly included in the 



sheath; fields, roadsides, waste places, common. 



Aug. -Sept M. jrondosa (Poir.) Fern. 



8. Internodes of the stem puberulent. 



10. Lemma short-pilose at base (on the callus) ; 



moist woods and thickets. Aug.-Oct. [M. 



joliosa sensu auth.] M. mcxicana (L. ) Trin. 



lU. Lemma not pilose at base; woods, chiefly in the 



s. and central parts of the state 



M. glabriflora Scribn. 



7. Glumes much longer than the lemma, awned ; panicle 

 dense, somewhat interrupted; wet ground. Aug.- 



Sept M. racemosa (Michx.) BSP. 



5. Lemma long-awned. 



11. Spikelets 3-4 ir.m long; glumes lanceolate, awn-pointed, 

 shorter than the lemma; anthers 1-1.5 mm long; rocky 

 woods. July-Oct M. tenuifiora (Willd.) BSP. 



