334 REPORT — 1900. 



e ice there was a long temperate interval during which 

 of Labrador, 700 miles to the north-east, must have been 



advances of the 

 even the heart 

 free from glaciers. 



II. The Pleistocene Flora of the Don Valley. By Prof. D. P. Penhallow. 



Special studies relative to the pleistocene flora of Canada have now 

 been carried on since 1889, the first report on the subject having been 

 made by Dawson and Penhallow in 1890.' Other contributions have 

 been made from time to time, but upon the occasion of the meeting of 

 the British Association at Toronto in 1897 a special impetus was given 

 to this work by the appointment of a Committee, to whom a grant was 

 made for the purposes of investigation, particularly in the neighbourhood 

 of Toronto. Under these favourable conditions much material has been 

 brought together, chiefly from the immediate vicinity of Toronto, and its 

 determination has thrown much important light upon the climatic con- 

 ditions of the various geological phases through which that region evidently 

 passed in interglacial times. During the past decade or more, other 

 important material has been gathered from various localities— often most 

 widely separated— throughout the Dominion. As the work of the 

 Committee is now practically completed, it is considered wise, in this 

 final report, to bring together all the information from these various 

 sources and endeavour to ascertain its bearing upon questions of current 

 interest and importance. 



Plants from eighteen special localities have been studied, ranging 

 from Manitoba to Cape Breton, and particular attention has been directed 

 to those from at least twelve of these locations, chiefly from the vicinity 

 of Toronto. 



Eighty-three species in all have been studied, the largest number from 

 any one locality (Taylor's Brickyard) being twenty-seven. In several 

 instances only one or two species have been obtained from a locality, in 

 which cases they afford no definite conclusions respecting the climatic 

 conditions of the locality ; but in other cases the character of the vegeta- 

 tion is such as to leave no room for doubt as to the climatic conditions 

 involved. In the Valley of the Don, numerous collections from the same 

 localities have resulted in a constant diminution in the number of dis- 

 coveries, until latterly the total absence of anything new has brought the 

 conviction that the flora of the region has been exhausted, and an in- 

 spection of the accompanying table will at once serve to disclose the extent 

 of the flora in each locality examined. The explorations of the past year 

 have added nothing new to our knowledge of the flora of these localities, 

 since the various plants found have proved to be only such as had been 

 previously determined. There is therefore little to be added to the 

 observations made in previous years, but attention may be directed to a 

 few considerations of interest which appear upon comparison of the various 

 localities studied. 



Of the eighteen localities under observation, five are so distant from 

 one another and from all others as to bear no obvious relation to each 

 other, or else the piant-remains are so few as to render them of little 

 value except from the general standpoint of geographical range. These 

 localities are Cape Breton, Rolling River (Manitoba), Solsgirth and Leda 



' Bxilh Geol, Soo. Amer. I. (18'.)0), pp. 311-334. 



