596 Forestry Quarterly. 



to the natural compactness of the prevailing loess. It would 

 seem that Schimper, and other foreign botanists, had a clearer 

 conception of the conditions in the treeless region for they per- 

 ceived the floristic and ecological differentiation of the great 

 plains and the prairies which the present author has failed to do, 

 since he uses the two terms interchangeably. 



It is, however, by the phytogeographical discussions that the 

 value of the present volume will be judged. The author states that 

 the classification of the North American continent into zones and 

 sections is to demark geographical locations, while the regions, 

 districts, areas and formations differentiate natural phytogeo- 

 graphical entities. With this statement clearly in mind, let us, 

 proceed to analyse Harshberger's conception of such distributional 

 groups of vegetation. 



The subarctic forest region of North Canada and Alaska is sub- 

 divided into the Labrador District, the Hudson Bay-Keewatin 

 District, the McKenzie District and the Alaska District. With 

 the exception of the last, where Pinus murrayana is substituted 

 for P. banksiana, and Abies lasiocarpa for A. balsamea, these 

 divisions seem to be merely geographical, at least so far as the 

 forest trees are concerned, and the differences in the other vege- 

 tation are not made clear in the text. The Atlantic section of 

 the north temperate zone is divided into three regions, namely: 

 the St. Lawrence-Great Lakes Region; the Atlantic-Gulf Coast 

 Region and the Piedmont-Appalachian-Ozark Plateau-Mountain 

 Region. The St. Lawrence-Great Lakes Region is further sub- 

 divided into the Maritime District and the Lake District. Practi- 

 cally the whole of New England and that portion of Canada south 

 of the subarctic forest and east of the Ottawa River are included 

 under the "Maritime District," while the region west to the prairies 

 is comprehended in the Lake District. By this arrangement the 

 forests of the Adirondacks and of the Green Mountains, practi- 

 cally identical in their composition, are placed in different phyto- 

 geographical entities. Surely this must be merely a geographic 

 division. 



The New Brunswick Area, a subdivision of the Maritime Dis- 

 trict, is made to include : "The northern portions of Maine, New 

 Hampshire, and Vermont (including their mountain ranges), its 

 southern boundary being determined by the southern limit of 

 Pinus banksiana, Picea alba, as well as the northern limit of the 



