206 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 



Frequent in lakes in the southern part of the valley. Lake Garfield 

 Monterey; Lake Buell, New Marlboro; Stoekbridge Bowl, Stock- 

 bridge. 



P. confervoides Reichenb. — In Guilder Pond on the Dome, Mt. 

 Washington, altitude 2000 feet. The only locality in the State for 

 this local Pondweed. 



P. dimorphus Raf. — In shallow water on sandy or gravelly bot- 

 tom ; frequent. Pontoosuc and Onota Lakes, Pittsfield ; 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 Stoekbridge. 



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, Stoekbridge; 

 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; Stoekbridge Bowl, 

 Stoekbridge. 



forma maximus Morong. — Housatonic River, Stoekbridge. 



forma myriophyllus (Robbins) Morong. — Harmon Pond, Shef- 

 field. 



forma terrestris Schlecht. — Muddy shores, Stoekbridge Bowl, 

 Stoekbridge. 



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; Stoekbridge Bowl, Stoekbridge; Prospect Pond, 

 Egremont; Harmon Pond, Sheffield. 



P. natans L. — Ponds and slow streams; common. 



P. Oakerianus 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- 



