415 



Poa eragrostis, Linn. 



hirsuta, Mx. 



nemoralis, Linn. 



nervata, Ww. 



pratensis, Linn. English-grass. Meadow-grass. 



reptans, Mx. 



serotina, Ehrhart. 



trivialis, Linn. Pasture-grass. 

 Podophyllum peltatum, Linn. Mandrake. May apple. 

 Pogonia ophioglossoides, Brown. Snake-mouth arethusa. 

 Polanisia graveolens, Rafinesque. 

 Polygala cruciata, Nutt. 



paucifolia, Ww. Flowering wintergreen. 



paucifolia v. alba, Eights. 



purpurea, Nutt, 



senega, Linn. Seneca snake-root, 



verticillata, Linn, Dwarf snake- root. 

 Polygonum amphibium, Linn. Mud knot-weed. 



arifolium, Linn. 



aviculare, Linn. Knot-grass. 



convolvulus, Linn. Bind knot-weed. 



fagopyrura, Linn. Buckwheat. 



lapathifolium, Linn. 



mite, Persoon. Tasteless knot-weed. 



pennsylvanicum, Linn. 



persicaria, Linn. Heart's ease. Lady's thumb. 



punctatum, Elliott. Water pepper, 



sagittatum, Linn. 



scandens, Linn. 



tenue, Mx. 



virginianum, Linn. 

 Polymnia canadensis, Linn. White leaf-cup. 



uvedalia, Linn. Yellow leaf-cup. 

 Polypogon racemosus, Nutt. 

 Pontederia cordata, Linn. Pickerel-weed. 

 Populus canadensis, Mx. 



candicans, Alton. Balsam poplar. 



