170 Transactions of the Canadian Institute. [Vol. VII. 



Near the edge of the cuesta, the breadth is sometimes over a mile, and 

 some of the valleys are remarkably flat-bottomed, occasionally with 

 gneiss outcropping in the floor, the sides being limestone. Very 

 frequently the bounding walls in the upper reaches are so steep that 

 they are in places unscalable. 



The intervalley spaces are flat topped, inclined gently southward at 

 a less angle than the dip, and have a thin, more or less discontinuous 

 covering of drift, rarely enough to significantly change the flat upland 

 topography. Some few of the intervalley areas, though flat topped, are 

 very narrow in parts, even to one hundred yards in width. 



The drift blocked equivalents of these valleys are found all the way 

 to the vicinity of Lake Simcoe and perhaps beyond. The upper 

 reaches along the Black River cuesta, are generally occupied by streams 

 or lakes. The Trent river, through part of its course, occupies portions 

 of several of these. The Bay of Quinte, itself a complex, ma}' be a 

 member of the series. 



The lower courses of all lie below the level of the first interglacial 

 deposits, and in some cases the lowest till sheet, overlaid by some of the 

 interglacial beds, is found within the valleys. They are thus either of 

 glacial or of preglacial origin. 



The axial direction of the drumlins in Hastings county, corroborated 

 by the direction of striae upon the inter-valley upland surfaces, indicates 

 that the direction of ice flow sometimes made an angle of about fifteen 

 degrees with the direction of these valleys. Sometimes, just at the edge 

 of the escarpment, striations are found on a curved rock surface bending 

 down obliquely into the valley. The best example is on Mill creek, 

 about two miles west of Sydenham. Occasionally in the valley bottom 

 striae are found which are not accordant in direction with those upon 

 the adjacent upland, but which nearly accord with the direction of 

 the valley sides, suggesting in some cases, local oblique motion beneath 

 the general ice stream. In other cases the direction of ice motion and 

 that of the valley coincide, x^s a rule the escarpments and valley-sides, 

 where the rock is exposed, are little, and generally not at all, scoured. 

 On the other hand, where there is a change in the direction, and the 

 valley is bounded by a steep rock wall, that cliff face is sometimes 

 polished smooth on the thrust side, but not elsewhere, in one case, near 

 Napanee, for over one hundred feet below the crest. The postglacial 

 retreat of the escarpments has been very small in some cases, and in 

 others nothing at all, there being no talus in some places, in others striae 

 rounding over the edge, or, again, the cliff presents a polished face. In one 



