104 ROCHESTER ACADEMY OF SCIENCE. [Oct. 8, 



896. S. humilis Marsh. X S. discolor Muhl. (?) 



Dry bank of Genesee river. Twenty plants in one group. 



897. S. sericea Marsh. Silky Willow. 



Wayne county, E. L. Hankenson . 



898. S. petiolaris J. E. Smith. 



Monroe county, Dr. C. Dewey. Wayne county, E. L. Hankenson. 



899. S. Candida Willd. [S. Candida Fliigge.] Hoary Willow. 



Cold swamps and sphagnum marshes; scarce. Marsh at head of 

 Irondequoit bay, Dr. C. M. Booth! Riga, Miss E. Beckwith. Adams 

 Basin, M. S. Baxter. Mendon, G. T. Fish. Caledonia, Livingston 

 county, Clinton. Bergen swamp, Genesee county. Wayne county. 



900. S. purpurea L. Purple Willow. 



Low grounds and along streams ; common . 



901. S. cordata Muhl. Heart-leaved Willow. 



In springy places on rocky river banks, ravine sides, low grounds and 

 along streams ; very common. 



902. S. cordata Muhl. X S. sericea Marsh. (S. myricoides Muhl.) 



Reported only by G . T. Fish. 



903. S. myrtilloides L. Myrtle Willow. 



Rare. Mendon, G. F. Fish ; M . S. Baxter, 1895. Wayne county. 



367. POPULUS Tourn. [L.] 



904. P. alba L. White Poplar. Abele. 



Roadsides; occasional. Produced by suckers from the roots of 

 planted trees. 



905. P. tremuloides Michx. American Aspen. 



River banks, ravines, hillsides ; common. 



906. P. grandidentata Michx. Large-toothed Aspen. 



Dry woods, river banks and hills ; common. 



907. P. balsamifera L. Balsam Poplar. 



Near the lake, in the town of Greece. Border of Bergen swamp. 



P. balsamifera L. var. candicans Gray. [F. balsamifera candicans 



(Ait.) A. Gray.] Balm of Gilead. 

 Occasionally planted along roadsides. 



908. P. monilifera Ait. Cottonwood. 



Frequent along the banks of the Genesee river and about Irondequoit 

 bay ; common along the shore of lake Ontario. Wayne county. 



909. P. dilatata Ait. [P. nigra L.] Lombardy Poplar. 



Bank of Genesee river, Greece. Frequently planted along roadsides. 



CERATOPHYLLACE/E. 



368. CERATOPHYLLUM L. 



910. C. demersum L. Hornwort. 



Frequent in all our bays and ponds. 



