72 THE CANADIAN NATURALIST. [Vol. X. 



On the northern side of the Dundas valley the escarpment after 

 reaching Copetown is buried by the drift. Although the line of 

 buried cliffs recedes somewhat to the northward of the Great 

 Western Railway, yet there are occasional exposures, as at Troy 

 and other places in Beverly and Flamboro, where the underlying 

 limestones come to the surface. At Harrisburg the limestones 

 are known to be absent for a depth of more than 72 feet, as shown 

 in a deep well in the drift. 



In the town of Paris one well came upon hard rock at 10 feet 

 below the surface, whilst another at 100 feet in depth reached 

 no further than boulder clay. This last well must have been in 

 a buried channel of Neith's Creek, as outcrops of gypsum-bearing 

 beds of the Onondaga formation frequently occur near the summit 

 of the hills. From what has just been written, it is easily seen 

 that the Niagara limestones are absent from a more or less horiz- 

 ontal floor (which is over 500 feet above the lake, on both the 

 northern and southern sides of the Dundas valley) which continues 

 from Dundas westward to near Harrisburg, where it meets a 

 portion of the Grand River valley. But almost immediately west 

 of Ancaster we find streams running northward at right angles 

 to the escarpment, and cutting through drift to the depth of 

 almost hundreds of feet. In fact, if we draw a line from Dundas 

 to northward of Harrisburg (a mile or two), and another from 

 Ancaster southward to the Grand River, we have two limits of a 

 reo-iou where the limestone floor has been cut awav from an other- 

 wise generally level region. The southern side of the area is the 

 southern margin of the Grand River valley, between Seneca and 

 Brantford ; and the western boundary is composed of Onondaga 

 rocks east of Paris (which perhaps forms an island of rocks buried 

 more or less in drift). 



The Buried River Charmel in the Dundas TaJley and its Ex- 

 tensions. That the Dundas valley is that of an ancient river 

 valley now buried to a great depth with the dehris produced in 

 the Ice Age, becomes apparent on a careful study of the region. 

 However, until a key was discovered the mystery of its origin 

 was found to be very obscure. My own labors at studying this 

 region may fairly be stated as the first systematic attempts at the 

 solution of the present configuration of the western end of Lake 

 Ontario and the adjacent valley. Assertions have been made 

 that it was scooped out by a glacier, but this wild hypothesis 

 was only a statement made without any regard to facts. 



