48 FLORA OF WORCESTER COUNTY. 



sericea, Marsh. Silky Willow. Common, 



cordata, Muhl. Heart-leaved Willow. Worcester. 



Prof. Eaton. 



myrtilloides, L. Leicester. 



POPULUS, Tourn. Poplar. 



tremuloides, Michx. American Aspen. Common. 



grandidentata,,Michx. Large-toothed Aspen. " 

 balsamifera, L., var. candicans, Gray. Balm of Gilead. 



Spontaneous, 

 monilifera, Ait. Cotton-wood. Rare. 



CERATOPHYLLACE.E. 



CERATOPHYLLUM, L. Hornwort. 



demersum, L. Slow streams. G. E. Stone. 



" " var. echinatum, Gray. " " " 



SUBCLASS II. GYMNOSPER1VLE. 

 CONIFERS. 



PINUS, Tourn. Pine. 



Strobus, L. White Pine. Common. 



rigida, Mill. Pitch " . " 



resinosa, Ait. Red " Templeton. V. P. Parkhurst. 

 PICEA, Link. Spruce. 



nigra, Link. Black Spruce. Not rare. 



TSUGA, Carriere. Hemlock. 



Canadensis, Carr. Quite common. 



ABIES, Link. Fir. 



balsamea, Miller. Balsam Fir. Northern part of the 



county. 



