70 TRIANDRIA.— DIGYNIA. 



HAB. ct. In pine-barrens. &. Sandy swamps, y. la 

 woods. <$\ Dry woods, e. Meadows. £ WoocU 

 and meadows. 



14. P. agrostuides : culm compressed, smooth, erect: 



leaves very long ; panicles lateral and terminal, 

 pyramidal, spreading ; branches racemiferous ; 

 spikelets appressed ; abortive floret neuter, with 

 the valves nearly equal. 

 HAB. Wet meadows. July— Sept. U . Culm 2—3 

 ft. high ; leaves numerous at the root ; pan. dark 

 purp. 



15. P. virgatum: whole plant very smooth; panicle 



diffuse, very large ; flowers acuminate ; valves of 

 the abortive floret nearly equal. 

 HAB. Margins of salt marshes. July — Aug. U . 

 Culm 3 — 4 ft. high ; leav. long^flat; pan. virgate ; 

 spik. large. 



16. P. anceps : culm compressed ; sheaths ancipitous, 



pilose ; panicle with nearly simple branches : 

 spikelets sub-racemose, much acuminate ; abortive 

 floret neuter, with the superior valve bifid. 

 HAB. Infields. July— Aug. U. Culm 3 ft. high : 

 leav. very long ; pan. pyram. ; spik. appress. 



J 7. P. rectum : panicle solitary, shorter than the termi- 

 nal leaf; branches simple, flexuous ; spikelets al- 

 ternate, peduncled, obovate, turgid ; giumes stri- 

 ate, acute ; leaves linear, straight, tapering to a 

 sharp point, striate and scabrous above, hairy be- 

 neath ; sheaths with very long hairs. 

 HAB. Banks of rivers, July. U . 



18. P. verrvcosum : culm slender, decumbent and genic- 

 ulate, branched below, and with the leaves smooth ; 

 panicle much spreading, few-flowered ; flowers 

 verrucose ; abortive floret 1-valved. 

 HAB. Swamps. Aug. U. Culm 18 in. high; nodes 

 smooth; leav. bright green; pan. lot. and term.; 

 fl. verrucose. 



Id. P. proliferum : culm assurgent, geniculate at base. 



very smooth ; panicles terminal and axillary ; 



smooth; spikelets racemose; abortive floret 1- 



valved. 



HAB. Wet meadows. Sept. U . Whole plant very 



