312 TRIANDRIA DYGINIA. 



E. canadensis : spike nodding at the extremity, patulous ; spikelets 3 

 - -5-flowered ; florets hairy; glumes linear-lanceolate. 



HAB. Banks of rivers. August, 9].; root creeping,- culm 3 ifeet 

 high; leaves dark green; spikes generally pendulous at the ex- 

 tremity. 



b. glaucifolius: leaves glaucous. 



HAB. Rocky shores. August. 



E. hystrlv : spike erect ; spikelets diverging ; calyx 0. 



HAB. Rocky hills. July, Tj.; culm 3 feet high ; leaves often glauc. 

 rach. Jlexuous ; spikes 3 at each joint ; calyx sometimes 1 %-leaved, 

 or a rudiment. 



63. ATHEROPOGON. 



A. apludoides : spikes racemose, distant, pendulous ; perfect floret with 



the inferior valve tricuspidate ; lateral bristles of the abortive floret 



half the length of the terminal one. 

 HAB. Rocky hills. August, 94. ; culm 18 inches high, assurgent ; 



leaves at length involute; spikes 20 40, oblong, sessile; anther 



red. 



64. PANICUM. Panic-grass. 



P. crus galli : racemes alternate and in pairs, compound ; rachis 5- 

 angled ; glumes terminating in hispid bristles ; sheaths glabrous. 



HAB. Along ditches and in cultivated grounds. August September, 

 <v) ; culm 2 4 feet high; leaves broad and flat; panicles dense ; 

 bristles sometimes wanting. 



P. latifolium : culm mostly simple, bearded at the joints ; leaves ob- 

 long-lanceolate, smooth, or with the sheaths, somewhat pubescent; 

 panicle terminal, a little exsert, simple, pubescent ; spikelets oblong- 

 ovate ; abortive floret antheriferous, 2-vaIved ; superior valve sub- 

 herbaceous, nearly as long as the inferior, acute. 



HAB. Woods and shady thickets. June July, 94-; culm I foot high; 

 leaves 1 inch broad; panicles about \5flowers, downy. 



P. nertosum: culm simple, nodes smooth; leaves broad-lanceolate, 

 smooth, a little ciliate on the margin; panicle much branched, 

 smooth, many-flowered ; spikelets oblong ; abortive floret antherif- 

 erous, with the superior valve subherbaceous, shorter than the in- 

 ferior. 



HAB. Boggy meadows. July, 9J.; culm 3 4 feet high, smooth; 

 leaves subcoriaceous ; panicle peduncle or sessile ; flower large. 



P. pubescens : erect, much branched, leafy, softly pubescent ; leaves 

 lanceolate, ciliate ; panicle small, few-flowered, free ; spikelets sub- 

 globose-obovate, pubescent. 



HAB. Woods and fields. June, 9J.; culm 18 inches high ; nddes hairy, 

 sheaths retrorsely ciliate ; panicles with horizontal branches. 



P. depauperatum : culm cespitose, hairy at the joints ; leaves linear- 

 lanceolate, smooth or hairy ; sheaths pubescent ; panicle few flow- 

 ered; branches in pairs, one of them 2-flowered, the other 1-flow- 

 ered. 



HAB. Barren sandy soils. May June, 1J. ; culm 1 foot high ; lower 

 leaves short ; panicles terminal, branches tortuous. 



P. nitidum : culm slender, simple, erect, smooth ; sheaths bearded at 

 the throat; leaves very few, broad-linear; panicle capillary rather 



