40 CATALOGUE OF PLANTS. 



P. balsamifera, L. (Balsam Poplar.) Abundant near streams. 



var. CANDICANS, Gray. (Balm of Gilead.) Commonly cultivated; never 

 spontaneous within this district, and perhaps European. 



[P. MONILIFERA, Ait. (Cotton-wood.) In cultivation from the West ; 

 rarely spontaneous ] 



[P. DILATATA, Ait. (Lombardy Poplar.) From Europe, in the pistillate 

 form only, and freely spreading by suckers.] 



Order 79. EMPETIlACE.ffi. Crowrerry Family, 



Empetrum, Tourn. Crowberry. 



E. nigrum, L. (Black Crowberry.) Moosilauke Mt., Rev. J. Blake. 



Order 80. CERATOPHYLLACE^. Hornwort Family. 



Ceratophyllum, L. Hornwort. 



C. demersum, L. Goose Pond in Canaan, George Pond in Enfield, N. H. ; 

 Fairlee Pond, Vt. ; etc. Not rare. 



