318 GEOLOGICAL SURVEY OP CANADA. 



Yar. pumilum, Gray. 



A very low and peculiar round-leaved form which extends north- 

 ward to the borders of British Columbia. (Gray.') 



(1463.) A. cannabinum, Linn. Indian Hemp. 



This species has nearly the same range as the last and the forms 

 vary just as much. Three forms of this species are likewise recognised. 



Var. pubescens, 



A. pubescens, Torrey Fl. I., 276. 



In the blown sand along the shore of Lake Erie at Point Pelee. 

 (Macoun.} Possibly not uncommon. 



Var. glaberrimum, DC. 



This, we take, as the common eastern form. All our specimens from 

 the older provinces are of this type. 



Yar. hypericifolium, Gray. 



A. hypericifolium, Ait. Hook. Fl. II., 52. 



Throughout Canada to the Saskatchewan. (Drummond.} Frequent 

 in grassy thickets from Manitoba to the Eocky Mountains and British 

 Columbia, All the forms of these two species should be collected and 

 examined, so that we may be enabled to speak decisively of their dis- 

 tribution. 



LXIII. ASCLEPIADACE^E. 

 391. ASCLEPIAS, Linn. (MILKWEED. SILKWEED.) 



(1464.) A. tuberosa, Linn. Pleurisy-root. 



Abundant in the vicinity of Belleville and westward towards Tren- 

 ton, Ont. ; Bice Lake Plains and northward into Peterboro' and 

 Yictoria counties. (Macoun.} Flamboro' near Hamilton, Ont. (Logie.} 

 Niagara Falls and Maiden. (Maclagan.} Vicinity of London, Ont. 

 (Burgess.} Lake Huron. (Dr. Todd.} Whirlpool, Niagara Eiver, and 

 at Strathroy, Ont. (McGill Coll. Herb.} 



(1465.) A. incarnata, Linn. Swamp Milkweed. 



A. amcma, Willd. Pursh. Fl. I., 181. 



In marshes and ditches quite common in Ontario. Keswick Valley, 

 N.B. (Prof. Bailey.} Lower Norton and Hammond Eiver, N.B. 

 (Brittain.} Charlotte County, N.B. ( Vroom.} Abundant from Quebec 

 westward to Owen Sound. (Macoun.} Lake of the "Woods. (Dawson.} 

 Throughout Canada to the Saskatchewan. (Drummond.} 



