166 Paniceae Panicum 



1.6 mm long; first glume about a third the length of the spikelet, 

 blunt, subacute. 



Blades stiff, erect 30. P. huachucae. 



Blades lax, spreading 30a. P. huachucae var. fasciculatum. 



Pubescence on upper surface of vernal blades long-pilose, ascending; first 

 glume about half as long as the spikelet, acuminate. .31. P. subvillosum. 

 Spikelets 2-2.5 mm long. 



Upper internodes shortened; leaves approximate, the blades often equaling the 



panicle; pubescence sparse and stiff 32. P. scoparioides. 



Upper internodes not shortened; the pubescence usually copious and rather silky. 

 Culms, sheaths, and lower surface of blades pilose but lacking short pubes- 

 cence; center of upper surface of blades not glabrous; spikelets about 2 



mm long; axis of panicle usually pubescent 33. P. villosissimum. 



Culms, sheaths, and lower surface of blades puberulent as well as pilose; center 

 of upper surface of blades glabrous; spikelets 2.1-2.5 mm long (usually 

 2.2-2.4 mm long) ; axis of panicle pilose 34. P. pseudopubescens. 



24. Panicum auburne Ashe. Map 297. Our only specimen is one col- 

 lected by Hill, July 8, 1913, in dry sand by a woods road at Dune Park, 

 Porter County. It is Hill's no. 7 and is deposited in the herbarium of the 

 University of Illinois. I have a duplicate of this number. 



Coastal Plain, Mass. to n. Fla. and La. ; Ark. and Ind. 



25. Panicum praecocius Hitchc. & Chase. Map 298. This species is rare 

 in the sands of the northern counties. I have, also, a specimen which was 

 found in Harrison County, about 3 miles east of Elizabeth on a rocky 

 wooded slope along the road leading from Elizabeth to Stuart's Landing 

 on the Ohio River. This rocky slope is rich in rare Indiana plants such 

 as Eragrostis capillaris. 



Mich, to Minn., southw. to Mo. and e. Tex. 



26. Panicum tennesseense Ashe. (Panicum languinosum var. septen- 

 trionale Fern.) Map 299. This is an infrequent grass found throughout 

 the state in various habitats. My specimens are from dry sands, moist 

 sand on the marly shore of a lake, wooded slopes, and hard, white clay soil 

 in a fallow field in the Wabash Bottoms. 



Maine, Que. to Minn., southw. to Ga. and Tex. ; westw. to Utah and Calif. 



27. Panicum albemaiiense Ashe. (Panicum meridionale var. albe- 

 marlense (Ashe) Fern.) Map 300. I have only one specimen of this grass 

 from Indiana and it is in the autumnal phase. I am not able to make a satis- 

 factory study of this species from the few specimens at hand. Some au- 

 thors refer it to a form of Panicum meridionale, to which it may belong. 

 It is found in sandy soils. 



Coastal Plain, Mass. to N. C. ; n. Mich., Wis., Ind. to Tenn. 



28. Panicum implicatum Scribn. (Panicum lanuginosum var. implica- 

 tum (Scribn.) Fern.) Map 301. Local to infrequent but common in its 

 habitat. It is generally found in moist, sandy soil on the marly borders of 

 lakes, in interdunal flats, and rarely in dry, sandy soil. 



I think this grass is restricted to the lake area and that all reports of 

 it from south of this area should be referred to some other species, most 



