206 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
Frequent in lakes in the southern part of the valley. Lake Garfield 
Monterey; Lake Buell, New Marlboro; Stockbridge Bowl, Stock- 
bridge. 
P. confervoides Reiehenb. — In Guilder Pond on tlie Dome, Mt. 
Wasliington, altitude 2000 feet. The only locality in the State for 
this local Pondwccd. 
P. dimorphus Raf. — In shallow water on sandy or gravelly bot- 
tom; frequent. Pontoosuc and Onota Lakes, Pi ttsficld; Shaw Pond, 
Otis; Lake Garfield, Monterey; Upper Spectacle Pond, Sandisfield. 
The form with crested fruit is the common form in the Pittsfield 
lakes. 
P. epihydrus Raf. — Ponds and brooks; common. 
var. cayugensis (Wiegand) Benn. — Cranberry and Crane Ponds, 
West Stockbridge. 
P. foliosus Raf. — In quiet shallow water; frequent. Muddy 
Pond, Washington; Pontoosuc and Onota Lakes, Pittsfield; Lake 
Buell, Monterey; Symon's Pond, Sandisfield; Mill River, New Marl- 
boro. 
P. Friesii Rupr. — Occasional; Konkapot Brook, Stockbridge; 
Mill River, New Marlboro. 
P. heterophyllus Schreb. — Ponds, on gravelly bottom; common. 
forma longipedunculatus (Merat) Morong. — On gravelly bot- 
tom in deep water. Richmond Lake, Richmond ; Stockbridge Bowl, 
Stockbridge. 
forma maximus Morong. — Housatonic River, Stockbridge. 
forma myriophyllus (Robbins) Morong. — Harmon Pond, Shef- 
field. 
forma terrestris Schlecht. — Muddy shores, Stockbridge Bowl, 
Stockbridge. 
P. hybridus Michx. — (P. diversifolius 111. Fl. ed. 2.) 
Plantin Pond, Mt. Washington. 
P. lucens L. — - Frequent in the southern part of the valley. Onota 
Lake, Pittsfield; Stockbridge Bowl, Stockbridge; Prospect Pond, 
Egremont; Harmon Pond, Sheffield. 
P. natans L. — Ponds and slow streams; common. 
P. Oake?ianus Robbins. — On upland ponds; occasional. South 
Pond, Savoy; pools in bog, Monterey; Spectacle Pond, Sandisfield; 
Guilder Pond, Mt. Washington. 
P. obtusifolius Mertens & Koch. — In cool ponds, on muddy bot- 
