GRAMINEAE 19 



11. P. perlongum Nash. A densely tufted perennial with smooth 

 culmsand hairy, long-linear leaves : primary panicle long-exserted, longer 

 than the leaves, few-flowered : secondary panicle 4-8-flowered on short 

 culms almost hidden by bases of the leaves : spikelets \\" long, nearly 

 smooth. On dry rocky slopes on the prairie between Greenwood and 

 Lee's Summit. Not common. May-June. 



12. P. virgatum L. 2-5 high : panicle 6 / -18 / long, with numer- 

 ous ascending branches, at length spreading or drooping : spikelets 

 2 // -2J // long : second scale very sharp pointed. Frequent throughout 

 in low, usually sandy ground. July-September. 



13. P. miliaceum L. MILLET. Stout culms l-2 high : leaves 

 S'-G' long with papillose-hispid sheath : panicle 4 / -6 / long, dense, more 

 or less included. Sparingly adventive along the railroads at Sheffield 

 and Courtney. July-August. 



14. P. proliferum Lam. Culms erect to decumbent, geniculate, 

 2-5 high : pyramidal panicle 4 '-20' long with numerous spreading 

 branches which are flower-bearing for about two-thirds their length : 

 spikelets \ ff long, green or purplish. Common along ponds and river 

 banks, and one of the commonest of weedy grasses along the streets of 

 Kansas City and other cities in the county. August-October. 



15. P. capillare L. WITCH GRASS. Culms 6 / -4 high, erect or de- 

 cumbent and often very geniculate : sheaths, culms and leaves very 

 hairy : terminal panicle at first included, at length exserted and widely 

 spreading, 6 / -14 / long with capillary branches. Common in waste 

 grounds, corn fields, etc. July- October. 



16. P. flexile (Gattinger) Scribn. Closely resembling the last, but 

 the leaves are narrower, smoother and more erect, the culm is strictly 

 erect, and the branches of the long, ovoid panicle are ascending and not 

 spreading. In dry grounds throughout. Not uncommon. July-Oc- 

 tober. 



17. P. cognatum Schultes. Culms decumbent, about 1 high : lower 

 sheaths and axils of the panicle hairy, otherwise smooth : leaves V-& 

 long, 2 /x wide : panicle 3 / -8 / long, ovoid in outline : branches capillary 

 and few-flowered, often 2' long and but 1-flowered : spikelets \\" long. 

 Sparingly introduced along the railroad at Courtney and Kansas City. 

 July-October. 



9. CHAETOCHLOA Scribn. 



Annuals. Spikelets as in Panicum, but with from one to several 

 bristles on the rachis below the point of attachment of the spikelet, the 

 bristles therefore persistent. July-September. 



Bristles downwardly barbed. 1. C. rerticillata. 



Bristles upwardly barbed. 



Spikes 4 X or more long, '-2' thick, noticeably com- 

 pound. 4. C. Italica. 



