FLORA OF THE UPPER SUSQUEHANNA. 101 



P. balsamifera candlcans (Ait.) A. Gray. Balm oi Gilkad. In 

 cultivalion throughout onr ranj2^e; occasionally escaped along 

 roadsides and banks of streams. ( /'. balsamifera, var. candi- 

 cans (rray. ) 



P. dilatata L. L(».mi;aki)Y PoI'i.ak. Often cultivated, and fre- 

 quently escaped along roadsides in the vicinity of dwellings. 



CERATOPHYLLACE/E. 



CKRATOPHVLLUM L. 



C. demersum L. Hornwort. Oxford; common, Coville. Lisle; 

 plentiful, Clute; Graves. Apalachin ; not rare, Fenno. The 

 only stations. Found in ponds and slow streams. Plant sub- 

 merged ; leaves cut into thread-like divisions, rendering it very 

 likely to be mistaken at a glance for various species of Chara. 



CONIFER/E. 



PINUS L. 



^ P. Strobus L. White Pine. Common and well known. 



P. rigida Mill. Pitch Pine. Torch Pine. Much less common 

 than the preceding. Rare in the Chenango valley. Found on 

 dry hillsides, seldom forming woods by itself as the white pine 

 does. Bark dark brownish-red; branches much less regular 

 than in the white pine. 



PICE A Link. 



P. Mariana (Mill.) B. S. P. Black Si'Rl«:e. Swamp at the 

 head of Christian Hollow, Bradford county. Pa. ; rare, Lucy. 

 Swamp near Thompson. Pa, ; not common, Graves. Near 

 Greene, N. Y. ; rare, Cltite. Brisbin swamp and at various 

 points in the northern part of Chenango county, always in 

 swamps, Coville. ( P. nigra Link. ) 



TSUGA Cark. 



T. Canadensis ( L. ) Carr. Hemlock. Very common. Often 

 forming extensive forests, especially in wet or rocky grounds. 

 A familiar tree. 



