360 Tlic Amcncan Geologist. June, isos 
be inferred from the statement, "N'ol less notable than the 
former continuity of the dissected upland is the want of sym- 
pathy between its surface and the structure of the rock masses 
of which the region is composed."* 
Concerning the rock texture in Connecticut and Massa- 
chusetts I know very little from direct observation; but for 
two seasons I worked in the type region of the highlands of 
New Jersey, climbing from valley to hilltop, and collecting 
rocks from all portions in a part of the western Highlands. 
, Wliile there are many low hills of hard rock, and possibly 
some of the higher ones composed of the less durable gneiss. 
1 there is, in that region, a very evident general sympathy, between 
the present topography and the rock texture. Where limestone 
or non-resistant^schist^nd gneiss exist, there are low hills and 
, valleys, while the coarser ancTmbre durable gneiss quite gen- 
,\erally mak^s the crests of the high hills. In other words, the 
I apparent remnants of the New Jersey highland peneplain in 
' Sussex county are really somewhat irregular hill tops com- 
< posed of durable, coarsely crystalline gneisses that have a gen- 
<■ eral uniformity of texture and power of resistance to subaerial 
denudation. So far as my observation goes, the conditions 
in Maine and Massachusetts are the same. 
Hence the small portion of the so-called peneplain still 
existing, and the only part upon which the argument for its 
former greater extension can be based, namely from 10 to 25 
per cent of the total area, is that in which the rocks are hard 
and rather uniform in durability. Therefore, although the 
rocks are complex in kind and position, they now stand in 
very general harmony with topography. To say that because 
of their hardness they now stand up at this level, while the 
remainder, being softer, has been lowered from th/ fomier 
condition of the peneplain, should be prefaced by pronf^iat 
this minute fraction of the supposed whole, in realit^t'^nvpre- . 
sents the remnant of such a plain. Neither the area occupied 
by the remnants, nor the nature of their rocks, seems tooear 
evidence of a conclusive kind in favor of the peneplain theory. 
It may be argued that one of the strongest bits of evidence 
in favor of the peneplain is not here considered. I refer to 
*Davis: Nat. Geog. Monog., 1896, vol. I., p. 271. 
