412 Canadian Record of Science. 



The Distribution and Physical and Past-Geo- 

 logical Relations of British North 

 American Plants. 



By A. T. Deummond. 



Some years since I had occasion to refer, .in some detail, 

 in this journal, to the leading features in the distribution 

 of plants in Ontario and Quebec. Since that time, not only 

 has a federal union of the whole country, from the Atlantic 

 to the Pacific, been consummated, but our knowledge of its 

 flora has been greatly extended, and it is now possible with 

 some reasonable degree of accuracy, to trace the range of 

 most of the pheenogamous or flowering plants, and of the 

 horsetails and ferns. The carices and grasses will still need 

 considerable attention from botanical explorers before it 

 will be possible to speak with confidence of their range. 



The great breadth here of the continent, extending from 

 Nova Scotia to British Columbia, and its varied physical 

 features and the climatic effects resulting from these, have 

 developed remarkable differences in the flora. There are 

 vast mountain ranges with numerous peaks of great height, 

 enormous stretches of wooded country, extending north- 

 ward to the extreme limit of trees, great areas of prairie 

 land and of park-like country, extensive inland seas of fresh 

 water, and a coast line of some thousands of miles, not only 

 within the northern temperate zone, but extending even 

 more largely within the Arctic circle. Such marked 

 physical conditions have necessarily given rise to differ- 

 ences in circumstances and climate, and have developed 

 distinctive floras, whilst the present connection of the 

 Dominion, along its southern boundary, with the northern 

 United States, and the past geological history of the 

 northern parts of the continent, have led to marked rela- 

 tions with the floras of foreign countries. It will be the 

 object of this paper to trace the connection of the general 

 flora of the Dominion with the floras of some foreign coun- 

 tries, to illustrate the distinctive floras of the different parts 

 of the Dominion, and to indicate the relations of these dis- 



