368 GEOLOGtCAL SURVEY OF OANABA. 



641. ARIS/EMA. 



(2406.) A. Dracontium, Schott.; Macoun, Ctit. IV., TB. 



On a flat in Delaware Township near London, Ont. 1889. {Mr. H. 

 D. Johnsm.) On an island in the Sydenham Eiver, near Strathroy, 

 Ont. (JDeamess.) 



642. PELTANDRA. 



(2407.) P. undulata, Eaf. ; Gray, Man., ed. VI., 72. 



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



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

 Ontario. 



647 LEMNA. 



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

 having the general appearance of L. minor, and with more than one 

 root was common "in ponds at Agassiz, B.C., May 20th, 1889. Foi- 

 the present 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 Ilaney, B.C. 1889. 

 (^Macoun.) 



648. WOLFFIA. 



(2415.) W. Columbiana, Karsten; Macoun, Cat. TV., 76. 



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

 \V. Brasiliensis, Weddell. 1889. (Bearness.) 



650. SACITTARIA. 



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



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

 (^Dawson.) In marshy spots subject to tide action along the lower 



