368 GEOLOGrCAL SURVEY OP CANADA. 



641. ARIS/EMA. 



(240G.) A. Dracontium, Schott. ; Macoun, Cat. IV., 72. 



On a flat in Delaware Township near London, Out. 1889. {Mi: IT. 

 D. Johnson.) On an island in the Sydenham Eivei-, near Strathroy, 

 Ont. {Dearness.) 



642. PELTANDRA.r 



(2407.; P. undulata, Rif. ; Gray, Man., cd. VI., 72. 



P. Virginica, Macoun, Cat. IV., 72. 



Very local in its distribution. Should bo looked for in western 

 Ontario. 



647 LEMNA. 



A species of this genus resembling Spirodela polyrrhiza in color, but 

 havinif the genei-al apjieai'ancc of L. minor, and witii more than one 

 root was common in ponds at Aga.ssiz, B.C., ilay 20th, 1889. P'or 

 the pi'csent this foi-m must remain without a name or number. 



795. SPIRODELA, Schleiden. 



(2414.) S. polyrrhiza, Schleid. ; Gray, Man., ed. VI., 552. 



Lemna polyrrhiza, Linn. ; Macoun, Cat. IV., 75. 



In still water at Sicamous, Agassiz, and Port Haney, B.C. 1889. 



(Macou7i.) 



648. WOLFFIA. 



(2415.) W. Columbiana, Karsten; Macoun, Cat. IV., 7(i. 



In a bay of Lake Ontario, west of Niagara Town, in company with 

 IF. i^rrt.svV/env.v, Weddell. 18Sfi. {i>earness.) 



650. SACITTARIA. 



(2418.) S. variabilis, Kngelm. ; Macoun, Cat. IV., 77. 



Abundant in the South Thompson River at Kamloops, B C. 1888. 

 (Dawson.) In marshj- spots subject to tide action along the lower 



