HOFFMANN: FLORA OF BERKSHIRE COUNTY. 207 



torn. Shaw Pond, Becket; Parish Pond, Otis; Crane and Cran- 

 berry Ponds, West Stockbridge; Three-mile Pond, Sheffield. 



P. pectinatus L. — Common throughout the southern part of the 

 County, in shallow muddy ponds and in the Housatonie River. In 

 Laurel Lake, Lee, it grows at the exceptional depth of six feet. Alti- 

 tude 1450 feet, IVIuddy Pond, Washington. 



P. praelongus Wulf. — In deep water (six feet) in lakes. Stock- 

 bridge Bowl, Stockbridge; Lake Garfield, Monterey; Harmon Pond, 

 New Marlboro; Three-mile Pond, Sheffield. 



P. pusillus L. — Shallow water in ponds and streams; common. 



var. tenuissimus Mertens & Koch. — Stockbridge Bowl, Stock- 

 bridge; Prospect Pond, Egremont. 



P. Robbinsii Oakes. — In shallow waterof ponds and lakes, through- 

 out the southern half of the County, generally associated with P. 

 pectivatus. A plant with a single perfectly developed fruit collected 

 in Pontoosuc Lake, Pittsfield. The steiile shoots form close mats 

 over the bottom. 



P. strictifolius Benn. — In quiet water of lakes; occasional. 

 Onota Lake, Pittsfield ; Stockbridge Bowl, Stockbridge ; Crane Pond, 

 West Stockbridge. 



P. Vaseyi Robbins. — In quiet water, Lake Garfield, Monterey. 



P. zosterifolius Schumacher. — (P. compressus 111. Fl. ed. 2.) 



Tn lakes and in the Housatonie River throughout the southern part 

 of the valley. 



JUNCAGINACEAE. ARROW GRASS FAMILY. 

 SCHEUCHZERIA. 



S. palustris L. — Sedgy borders of peat bogs; rare. Sheffield; 

 Monterey. 



ALISMACEAE. WATER-PLANTAIN FAMILY. 

 ALISMA. Water-plaxtaix. 



A. Plantago-aquatica L. — {A. subcordatum 111. Fl. ed. 2.) 

 Muddy shores and ditches ; common. 



SAGITTARIA. Aukow-hkad. 



S. arifolia Xutt. — Shallow water; occasional. Onota Lake, 

 Pittsfield; swale near Housatonie River, New Lenox; brook, Stock- 

 bridge; river fiats, Sliellield (Clmrchiil). 



