478 S. FRAGiLis L. (Crack Willow.) Near Mocanaqua, Dudley. Planted 



for protection to river banks. 



479 S. ALBA L., VAR. viTELLiNA. (White Willow.) Frequent in Wyoming 



Valley. 



480 S. ALBA, VAR. CAERULEA Koch. Along Susquehanna, Dudley. 



481 S. BABYLONicA L. (Weeping Willow.) Cultivated and escaped. 



482 S. LONGiFOLiA Muhl. (Sand Bar Willow.) Sand bars of Susquehanna 



River. 



483 S. CORDATA Muhl. (Heart-Leaved Willow.) Frequent in two valleys. 



484 S. CORDATA, VAR. MYRicoiDES Carey . Toby's Creek, Kingston, Thurs- 



ton. 



485 S. GLAUCOPHYLLA Bebb. (Broad-Leaved Willow.) Monroe County, 



Prof. Porter. 



486 S. DISCOLOR Muhl. (Glaucous Willow.) Frequent in wet places on 



mountains. 



487 S. PETioLARis Sm. Abundant at Moosic Lake. 



488 S. HUMiLis Marsh. (Prairie Willow.) Frequent. 



489 S. TRisTis Ait. (Dwarf Gray Willow.) Campbell's Ledge, opposite 



Duryea. 



490 S. SERicEA Marsh. (Silky Willow.) Frequent in Lackawanna Valley. 



491 S. ROSTRATA Richards. Pocono, Penobscot, Wilkes-Barre. 



492 S. INCANA. Kingston, Thurston. Escaped from cultivation.* 



POPULUS L. (Aspen) 



493 P. ALBA L. (Silver-Leaved Poplar.) Cultivated and spreading by 



root. 



494 P. TREMULOiDES Michx. (Quaking Aspen.) Common. 



495 P. GRANDiDENTATA Michx. (Largc-Toothcd Aspen.) Frequent. 



496 P. CANDICANS Ait. (Balm of Gilead.) Rarely spreading from cultiva- 



tion. 



497 P. DELToiDES Marsh. (Carolina Poplar.) Commonly spreading from 



the roots. 



498 P. NIGRA, VAR. iTALicA Du Roi. (Lombardy Poplar.) Kingston flats. 



MYRICACEAE (Sweet Gale Family) 

 MYRICA L. 



499 M. GALE L. (Sweet Gale.) Lake Henry, Waymart, Naomi Pines. 



500 M. CAROLiNENSis Mill. (Bayberry.) Monroe County, Prof. Porter. 



501 M. ASPLENiFOLiA L. (Swcet Fern.) Common. 



JUGLANDACEAE (W^alnut Family) 

 JUGLANS L. (Walnut) 



502 J. ciNEREA L. (Butternut.) Frequent in Abington and Spring Brook 



503 J. NIGRA L. (Black Walnut.) Not uncommon. 



CARYA Nutt. (Hickory) 



504 C. OVATA Koch. (Shell-Bark Hickory.) Frequent. 



505 C. ALBA Koch. (White-Heart Hickory.) Frequent. 



506 C. MicROCARPA Nutt. Mocanaqua. 



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