2i8 The American Geologist. April, i899 
sented (p. 359), and in evidence of this doubt it is said that 
in the Highlands of New Jersey there is "a very evident gen- 
eral sympathy between the present topography and the rock- 
texture" (p. 360). There is some danger that our discussion 
may here run into cross purposes, for this objection to pene- 
planation does not meet the arguments advanced in its favor. 
Disregarding the weaker structures, which are now worn down 
beneath the inferred surface of the peneplain, it seems to me- 
undeniable that the peneplain surface was strongly discordant 
with the hard structures that still preserve its remnants. It 
is a matter of necessity that the present topography of an up- 
lifted and dissected peneplain should exhibit sympathy be- 
tween form and structure, for where should better accordance 
of form and structure be expected than in such a region of 
adjusted drainage; but this is a matter quite apart from the 
present discussion. 
Various gneisses, sandstones, and trap sheets, standing in a 
more or less inclined position, are truncated with good ap- 
pearance of system by the gently slanting surface of the pene- 
plain of northern New Jersey. The following description of 
the region is taken from one of Cook's reports. "The High- 
land mountain range consists of many ridges which are in 
pait separated by deep valleys and in*^ part coalesce, forming 
plateaus or table-lands of small extent. . . . rV character- 
istic feature is the absence of what might be called Alpine 
structure [form-?] or scenery. There are no prominent peaks 
or cones. The ridges are even-topped for long distances and 
the average elevation is uniform over wide areas. Looking at 
the crests alone and imagining the valleys and depressions 
filled, the surface would approximate to a plane gently in- 
clined toward the southeast and toward the southwest" (Geol. 
Surv. N. J., Ann. Rep. 1883, 2.J. See' also p. 28, 29. 6d, 61) 
It is this indifference of the peneplain to the various structures 
that it systematically truncates that has always been the chic<' 
argument of those who thought they saw traces of a former 
lowland where there is to-day a dissected highland, whether 
'.liey believed in marine abrasion or in subaerial denudation. 
Special mention may be made here of certain features that 
will be referred to more briefl\- in a later section (C 4). De- 
scending the Hudson froiv -^"'•ev.yerstraw to ]ersev Citv, one 
