202 The American Geologist. April, i89o 
the Connecticut valley by footprints and other fossils. The 
Connecticut sandstones are hence the original pattern by 
which we are to judge of the dimensions and qualities of all 
the other terranes. What can be more fitting than to make 
this original pattern the standard of comparison for all the other 
Triassic areas? It seems inappropriate, however, to attempt 
to use either local designation for any of these rocks west of 
the Mississippi. 
THE GLACIAL GEOLOGY OF THE IRONDEQUOIT REGION 
By Charles R. Deyei:, Fort Wayne, lud. 
At the very head of the great bight on the south shore of 
lake Ontario opens the mouth of a narrow gorge which extends 
some ten miles into the land. The lower half of it is occupied 
by the waters of Irondequoit ba}', the mouth of which is one 
mile wide and now nearly closed by a sand bar. The bay 
rapidly narrows to less than half a mile, but in its upper half 
abruptly widens to three-quarters of a mile. Above the head 
of the bay the gorge is prolonged southward to the village of 
Penfield, but there is no evidence that the bay ever occupied 
the whole of it. The walls rise on either side to a bight of 
170 feet and are everywhere of drift worn into characteristic 
forms of knob and peak. The lateral ravines in the upper 
half of the bay reveal the presence of Clinton and Niagara 
shales and limestones a few hundred feet back from the shore 
and rising nearly to the level of the country on either side. 
The real phenomenon to be considered, then, is a rock gorge 
partially filled and marked by drift. Its limits can.be approx- 
imately outlined and prove to enclose a space one mile wide 
at the top ; the depth of the drift at the bottom is unknown, 
but the bay is in some places 70 feet deep, so that the total 
depth of the gorge can not be less than 250 feet. It is boat- 
shaped and resembles the basins of the "finger lakes." It is 
blocked at the south end by a precipitous wall of drift, so that 
its actual length can be determined only by boring. The 
Irondequoit river enters at the southeast corner by a series of 
rapids. 
Twenty miles south of the head of the bay the Irondequoit 
basin is enclosed by a glacial moraine of strong features and 
" American Geologist, March, 1889, p. 178. 
