1881. ] Geology and Paleontology. 409 
square miles, where the drift is found to a great depth, forms the 
western extension of the Dundas valley. With the north-western 
and western portions of this drift-filled area, the upper portions 
of the Grand river and Neith’s creek were formerly connected. 
The Grand river from Brantford to Seneca runs near the southern 
boundary of this basin, then it enters the old, valley which ex- 
tends from Seneca to Cayuga, with a breadth of two miles, and a 
depth in modern times of seventy-five feet, having its bed but a 
few feet above Lake Erie. However, along the eastern margin of 
this valley, near Cayuga, we find that the rock is absent even to 
a depth below the surface of Lake Erie. 
2. The Dundas valley and the country westward forms a por- 
tion of a great river valley, filled with drift. Along and near its 
present southern margin this drift has been penetrated to 227 feet 
below the surface of Lake Ontario, thus producing a cafon with a 
lateral depth of 743 feet, but with a computed depth in the mid- 
€ of its course of about 1000 feet. 
3. The Grand river, at four miles south of Galt, has, since the 
Ice age, left its ancient bed, which formerly connected with the 
Dundas valley, as did also Neith’s creek, at Paris. 
4. Lake Erie emptied by a buried channel, a few miles westward 
of the present mouth of the Grand river, and flowed for half a dozen 
miles near Cayuga, where it entered the present valley, and con- 
tinued in its channel (reversed) to a place at a short distance west- 
ward of Seneca, whence it turned into the basin referred to above, 
uron. 
5. Throughout nearly the whole length of Lake Ontario, and 
at no great distance from its southern shore, there is a submerged 
¢scarpment (of the Hudson river formation), which in magnitude 
's comparable with the Niagara escarpment itself, now skirting 
the lake shore. It was along the foot of this escarpment that the 
river from the Dundas valley flowed (giving it its present form) 
to eastward of or near to Oswego, receiving many streams along 
its course, 
6. The western portion of the Lake Erie basin, the south- 
western counties of Ontario, and the southern portion of the 
basin of Lake Huron formed one Preglacial plane, which is now 
covered with drift or water (or with both) to a depth varying from 
river, and entering the Erie basin, between Port Stanley and 
