(2412.) L. trisulca, Linn.; Hook., Fl. II., 169; Pursh, Fl. I., 22.

Abundant in many ponds from the Atlantic to the Pacific. Ponds Windsor, N.S. (Macoun.) Petitcodiac, N.B. (Fowler, Cat.) Abundant around Ottawa. (Fletcher, Fl. Ott.) Conway's Creek and other places near Prescott Ont.; common. (Billings.) Very abundant in all still waters throughout central Ontario. (Macoun.) Common in marshes at Hamilton, Ont. (Buchan.) Marshes at Kingston, Ont. (Millman.) Small lakes, Red River prairie and Lake of the Woods, 49th parallel. (Dawson.) Ponds, Souris Plains, Assiniboia. (J. M. Macoun.) In ponds throughout the prairie region, on the Cypress Hills and north to Peace River and Little Slave Lake; common in ponds and quiet rivers at Cedar Hill, Nanaimo, and Alberni, Vancouver Island. (Macoun.) Canada to lat. 58°. (Hooker, Fl.)

(2413.) L. minor, Linn.; Hook., Fl. II., 169.

; Pursh, Fl. I., 22.

Frequent in ponds from the Atlantic to the Pacific. Magdalen-Islands, N.S. (McKay.) In ponds at Truro, and in ditches at Pictou, N.S. (Macoun.) Petitcodiac, N.B. (Fowler, Cat.) Vicinity of Ottawa. (Fletcher, Fl. Ott.) Conway's Creek and other places near Prescott, Ont.; common. (Billings.) Very common in ditches and shallow pools throughout central Ontario. (Macoun.) Marshes near Hamilton, Ont. (Buchan.) Common in the Lake of the Woods and in small ponds on the Red River prairie. (Dawson.) Abundant in pools throughout the whole prairie region, extending northward to the Athabasca and Peace rivers, and westward to Quesnel, on the Fraser River, and throughout Vancouver Island. (Macoun.) Canada to lat. 58°. (Hooker, Fl)

(2414.) L. polyrrhiza, Linn.; Hook., Fl. II., 169; Pursh, Fl. I., 22.

Spirodela polyrrhiza, Schleid.; Coult. Rocky Mount. Flora, 360.

Scarcely so common as the other, but just as widely distributed. In still water near Louisburg, Cape Breton. (Macoun.) Sussex, N.B. (Fowler, Cat.) Common around Montreal, 1821. (Dr. Holmes.) Common in still water around Ottawa. (Fletcher, Fl. Ott.) Conway's Creek and other localities near Prescott, Ont. (Billings.) In ponds, Gananoque, Ont. (Prof. Fowler.) Marshes and ponds everywhere throughout central Ontario, especially in the still waters of the River Trent, and Rice Lake. (Macoun.) Marshes at Hamilton, Ont. (Buchan.) Pelee Point, Lake Erie. (Burgess,) Stagnant pools near London,. Ont. (Burgess, Millman.) Occasionally in pools and still waters west of Porcupine Mountain, Man., and westward to Little Slave Lake; rather rare on Vancouver Island, but not uncommon at Alberni, on the west coast. (Macoun.) Cumberland House, on the Saskatchewan. (Hooker, Fl.)