44 BOTANICAL GAZETTE [JANUARY 
4. The character of the forest as a whole is stable, though any 
given area is continually changing in composition and relative 
proportions of the various species. 
VY. The same type of forest, with local differences in some 
places, is probably the climax throughout the northeastern conifer 
region. 
VI. Comparison with the conifer-birch forest of the southern 
Appalachian summits shows a striking equivalence of species and 
marked correspondence between the two in ecological character- 
istics, indicating that the forest dynamics are essentially the same. 
The mountain forest may logically be considered as a southward 
extension or outlier of the northeastern climax forest. 
.VII. Acer saccharum is dominant upon the main ridge at the 
southwestern end of Isle Royale, reaching here its extreme northern 
limit in this region. Southward it is probably able to supersede 
the conifers and birch, while north of its northern limit the suprem- 
acy of the latter trees is undisputed. 
Pato Ato, CALIFORNIA 
s Sei a aes 
