No. 386. THE PENEPLAIN. ee 
33 
between these terranes and that underlying the peneplain. 
Whether ‘structure’? means “ position ” alone or “ position ” 
plus “texture ” (as it manifestly ought not to do), we cannot 
agree with the statement. The granites, granitites, syenites, 
and quartz porphyries of Osceola, Tripyramid, the eastern 
Kearsarge, Red Hill, and the New Hampshire Whiteface, are 
entirely different in structure and mineralogical characters from 
the foliated rocks of Massachusetts or even the batholites of 
coarse porphyritic granite of New Hampshire and Massachu- 
setts, and we believe that no practical worker in the field rela- 
tions of these areas finds difficulty in putting in similar contrast 
the Massachusetts foliated rocks and the heavier, more massive 
gneisses and schists of the White Mountains proper. Is the 
structure of the Adirondack granite massif “ similar ” to that of 
the Berkshire plateau, the structure of Mount Ascutney, Ver- 
mont, with its three great stocks of deep-seated intrusives, ‘simi- 
lar’’ to the structure of the surrounding phyllites and gneisses, 
or that of the granitic Katahdin “similar ” to the Calciferous 
slates through which the granites came? 
Professor Tarr goes on to say that he has stood on the 
“higher ” peaks of Maine and looked in vain for any series of 
peaks that even to the eye appeared uniform in level. For any 
one to advance this observation as an argument against the 
New England peneplain seems to us quite incomprehensible. 
To look for a fairly chosen peneplain sky-line a thousand feet 
or two thousand feet above the level at which the advocates of 
the peneplain ask us to find it, and to look for that sky-line in 
a nest of granitic monadnocks, is hardly likely to be the mode 
of procedure by which to successfully attack the theory of the 
peneplain. 
He questions any serious lack of “sympathy between the 
level-topped hills and the rock texture and position.” He 
notes the fact that the soft gneisses and the limestones of New 
Jersey lie in regions of average lowland, and the hard gneisses 
underlie areas of greater elevation. This is the sole argument 
he makes to support this lack of sympathy. He then states, 
without the shadow of proof, that, “although the rocks are 
complex in kind and position, they now stand in very general 
