208 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 



S. graminea Michx. — Lake shores; occasional in the valley. 

 Onota Lake, Pittsfield, submersed; gravelly shore of Richmond Lake, 

 Richmond, emersed; Stockbridge Bowl, Stockbridge. 



S. heterophylla Pursh, forma fluitans Blake. — Vid. Rhodora, 

 15: 159 (1913). (S. rigida 111. Fl. ed. 2.) 



Leaves all linear, or phyllodial and bladeless. 



Shallow water of ponds; occasional. Stockbridge Bowl, Stock- 

 bridge; Crane Pond, West Stockbridge; Guilder Pond, Mt. Washing- 

 ton, altitude 2000 feet. 



S. latifolia Willd. — Muddy shores and swamps; common. Five 

 forms of this variable species occur in Berkshire County. The type 

 form has been collected in Cheshire (Winslow) and North Adams 

 (Fernald and Long). 



forma diversifolia (Engelm.) Robinson. — Borders of lakes; fre- 

 quent. 



forma gracilis (Pursh) Robinson. — Shallow water, borders of lakes 

 and streams; frequent. 



forma hastata (Pursh) Robinson. — Shallow water; common. 



forma obtusa (Muhl.) Robinson. — Swamps and riverbanks; fre- 

 quent. 



HYDROCHARITACEAE. FROG'S BIT FAMILY. 



ELODEA. Water-weed. 



{Philotria 111. Fl. ed. 2.) 



E. canadensis Michx. Water-weed. — Shallow water in ponds 

 and streams; ccrmmon in the valley. 



VALLISNERIA. Eel Grass. 



V. americana Michx. Eel Grass. — ( F. spiralis Man. ed. 7; 

 vid. Rhodora, 20: 108, 1918.) 



Shallow water of ponds and in the Housatonic River; frequent. 

 Onota Lake, Pittsfield, covering the sandy bottom densely over many 

 acres, turning reddish in September and browning the surface of the 

 water; Stockbridge Bowl, Stockbridge; Crane Pond, West Stock- 

 bridge; shallow lagoons of the Housatonic River from Stockbridge to 

 Sheffield. 



