Association of American Geologisis and Naturalists. 171 
tide might have prevented any horizontal deposition far out from 
the margin ; and thirdly, that a gentle and steady rising of the 
region would, in conjunction with the proximity of the channel, 
tend to maintain both the slope of the sediment and the lateral 
advance of the shore which the hypothesis requires. 
Mr. Benjamin Silliman, Jr., referring to the formation of the 
Connecticut valley only, considered a part of the present inclina- 
tion of the beds to be the result of upheaval, connected with the 
outbursting of the trap. 
Prof. W. B. Rogers made some remarks corroborating the 
views of Prof. H. D. Rogers in their application to the middle 
secondary or new red sandstone strata of Virginia and North Car- 
olina. He described this group of rocks, consisting of shales, 
slates, sandstones and conglomerates of various tints of red and 
gray, as extending with some considerable interruptions in a nearly 
8.8. W. direction, entirely across the State of Virginia, and for 
some distance into North Carolina. With but a few local excep- 
tions he had found the dip throughout this belt to be N. W. or 
N. N. W. Though destitute of the wide and prolonged ridges 
of trap met with in the corresponding districts of Pennsylvania 
and New Jersey, this region includes a great number of small 
dykes and knobs of trappean rock, penetrating the sedimentary 
strata, but in no instance causing any well marked change of dip 
in the adjacent beds. The materials of these strata Prof. R. 
stated to be very clearly traceable to the region of gneissoid and 
schistose rocks lying to the southeast of the tract, and in some 
cases, as in the limestone pebbles included in the conglomerate, 
could even be referred to the individual beds from which they 
thad been torn. = if ; ee 
He supported the opinion maintained for some. years past by 
Prof. H. D. Rogers, that the inclination of the strata is not due 
to a tilting action. subsequent to their deposition, +" the simple — 
consequence of the influx of detrital matter from e southeast, 
and its deposition in a series of northwest-dipping planes. As 
greatly favoring: this view he mentioned the fact generally ob- 
served in this belt throughout Virginia, that the strata become 
Steeper in their inclination as we proceed towards the northwest ; 
whereas the reverse should have been expected from a force tilt- 
ing them from a horizontal or gently inclined position into the 
present northwestern dips. This opinion he conceived, was still 
