PLANTS AND FERNS. 81 



PoPULUs trem^iloides, Mx. American Aspen, Ap. Ij 20 — 30 ft. 



Woods. . 

 P. grandhlentata^ Mx. Ap. ij 40 — 50 ft. 

 P. angidata, Ait, Cotton-wood. Ap, Ij 60 — 80 ft. Banks of 



streams. 

 P. dllafafa, Ait, Lombardy Poplar, Ap. >2 50 — 80 ft. Naturalized. 

 PoRCELiA triloba, P. Custard Apple. Papavv. p. Ap, h 20 — 40 



ft. Woods. 

 PoRTULAccA oJerttcea, Linn. Purslane, y. J. Prostrate. Road 



sides. 

 PoTAMOGETON nutans, Linn. g. Ju, ^ Water, Upper leaves 



floating. 

 P. perfoliatiwi, Linn. g. Ju, 2/. Water. Submersed. 

 P. lucens, Linn. g. J. ^ Water. Submersed. 

 P. gramineum, Mx. g. Ju, ^ Water. Submersed. 

 P. zosterifolium, Schum. g. Ju. J^ Submersed. 

 PoTENTiLLA norveglca, Linn. Cinquefoil, y. J. lo — 18 i. 



Fields. 

 F. canadensis, Liim. Five-finger, y. M. ^ 2 — 18 i. Procumbent. 



Road sides. 

 F.comarum,I)ec. p. J. 21 12 — 18 i. Swamps. Comk-rvu palustre, 



Linn. 

 Prenanthes alba, Linn. y-iv. Au, ^ 2 — 4 ft. Woods, 

 P altissima, Linn. _p-?/. Au. ^ 4 — 6 ft. Woods. 

 P. delloidea, Ell. J5, Au. 21 2 ft. Rocky woods. 

 Prinos verticiUatus, Linn, False Alder, to. J. 13 4 — 8 ft. Swamps. 

 Prunella t'2<7ifaris, Linn. J9. J. 21 6 — 12 i. Fields. 

 Prunus virginiana, Linn, Wild Cherry, w. M. I2 30 — 60 ft. 



Woods. 

 P. seroima, Ehr. iv. 3. \i 10— -20 ft. Woods. 

 P. americana, Marshall. Wild Plum. ?«, M, Ij 10— 20 ft. 

 Pteris aquiUna, Linn. Ju. J^ 1—2 ft. Woods. 

 F. atropurpureaiLmn. Ju. ^ 6 — 12 i. Rocks. 

 PuLMONARiA virginictt, Linn, b. M, ^ 1 — 2 ft. Low woods. 

 Pycnanthemum incanum, Mx, r-?w. Ju, 2J^ 1 — 2 ft. Woods, 

 Y.linifoVmm^Vh.. to, Ju, 2/ 1 — 2 ft, Open woods, 

 F.lanceolatum,?\\. to. J. 21 12 — 18 i. Woods. 

 Pyrola rotundifolia, Linn. to. J. 21 6 — 12 i. Woods, 

 V.eUiptica,'N. to. 3. 21 6— 10 i. Woods, 

 P, secunda, Linn. g-to. Ju, 21 6 — 8 i. Woods, 

 T. asarifolia,Mx. g-to. Ju, 2/ 3— 12i. Dry woods. 

 F. chhrantha, Sw.} g-to. Ju. 11 10 i. Dry woods. 

 11 



