CONTRIBUTIONS TO THE PLEISTOCENE FLORA 

 OF CANADA 



D. P. PENHALLOW 



Eaely in the present year I received from Professor A. P. Cole- 

 man of Toronto University, a very fine collection of leaves from 

 the Interglacial deposits of the Don Valley, Toronto. With them 

 there was one small but rather well preserved fragment of a woody 

 branch which it was possil)le to identify with accuracy. These 

 specimens prove to be important since they serve to confirm in 

 rather striking ways, conclusions already reached through previous 

 studies of the Don material, and they furthermore afford addi- 

 tional evidence bearing upon the preglacial existence of types 

 now unknown in the living state. It is therefore thought desirable 

 to place on record such facts as are revealed by a study of this 

 collection. 



The last previous record of the Don plants was made by me in 

 1904 ('04) when thirteen species were passed in review. Since 

 then both Berry ('06) and Rollick ('06) have added to our knowl- 

 edge of the Pleistocene of Virginia and Maryland, and the evidence 

 they bring forward goes to show that essentially the same flora 

 characterized the entire region between Virginia and Ontario in 

 Pleistocene time. The following species are included in the 

 present studies: — 



Acer pleistocenicum Penh. — This species appears for the fourth 

 time in collections from the Don Valley, and in the present instance 

 it forms a large percentage of the entire material. ]\Iost of the 

 specimens are in fragments, but one or two are nearly perfect. 

 One of the best of these is reproduced here on a diminished scale 

 ir^ (Fig. 1), as it is more complete than that employed for the original 

 S description ('90, 327). 



(y^ In the last enumeration of Canadian Pleistocene plants ('04, 72), 

 ^ attention was directed to the very close resemblance between Acer 

 ^ pleistocenicum Penh., and .4. lesquereuxii Knowlton ('98) and the 

 CD opinion was then expressed that the two are undoubtedly the 



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