134 THE AMERICAN NATURALIST. [VoL. XXXIII. 
harmony with topography.” In the next paragraph he admits 
that “the region is a lowered mountain mass, evidently once of 
a very rugged topography, but now much reduced and traversed 
by drainage lines of a somewhat mature form, the result of ele- 
vation.” But that there be or not a lack of sympathy between 
structure and land-form will evidently depend, among other con- 
ditions, upon the degree of the lowering. The make-up of the 
New England upland certainly indicates the former existence 
in the district of massifs of flexed rocks at least as imposing 
from their altitude as the modern Alps (one resulting conclu- 
sion from the detailed work of Emerson in western Massachu- 
setts, of Shaler and Woodworth in the faulted and folded 
region of Narragansett Bay, of Pumpelly, Wolff, and Dale in the. 
Green Mountain axis, to say nothing of the older work of the 
Hitchcocks and others). Where are the ridges corresponding 
to the folds of the Boston Basin, or the fault-scarps of Rhode 
Island or of the Connecticut Valley? It is, in other words, im- 
possible to speak of sympathy between the topography and the 
structures of New England, when the latter demand displace- 
ments of thousands of feet, especially in view of the fact that 
the valleys and hills of the upland run at all angles to the axes 
of folds or the lines of fault. There zs some sympathy between 
topography and the hardness of the rock-members, but it is 
only with the extremest rarity that there can be traced any cor- 
respondence of structure (position) and the land-form in New 
England outside-of the Narragansett Basin or the Triassic 
lowland. 
The evident adaptation of many of the valleys and broader 
lowlands of New England to the superior softness of the rocks 
they cover is just what we should expect to find on any theory 
of New England topography that recognizes a period of uplift, 
recent, but long enough ago to allow of the excavation of the 
valleys to their present levels. This uplift Professor Tarr 
acknowledges, but claims that “there is no evidence to prove” 
that this uplift has been differential, that is, that there has been 
-a tilting toward the southeast. If there has been no such tilt- 
ing, it is necessary, following Professor Tarr, to consider that 
while the Deerfield has cut its canyon-like valley, and is still 
