142 PROCEEDINGS OF WASHINGTON MEETING. 



New York. — Remarkable scantiness of drift characterizes parts of Henderson, 

 Hounsfield, Brownville, Lyme, Clayton and other townships of Jefferson county, 

 New York, bordering the eastern end i>i' Lake Ontario, seen by me last autumn 

 during surveys with Mr. < '<. K. < rilbert on the beaches of the glacial lake Ontario 

 or Iroquois. Tins tract differs widely in topography and geology from that cited 

 in Massachusetts; for it has a flat, very gently inclined surface, and consists of 

 nearly horizontal beds of the Trenton limestone. The roads often run long dis- 

 tances on the nearly level solid rock; and the soil of the fields, though supplying 

 good pasturage and cultivated crops, is only a few inches or in its deepest parts a 

 few feet thick. This almost continuous but very thin mantle of drift appears to 

 have been chiefly englacial, the bottom of the ice having rested on the rock. 

 Within a distance of a few miles eastward, however, the drift has a considerable 

 depth, and is here and there heaped in beautiful oval drumlins, which rise 50 to 

 100 feet or more above their base. 



Minnesota. — A much larger area having surprisingly scanty drift deposits lies 

 north and east of Vermilion lake. Minnesota, consisting of Archean schists with 

 very hilly contour and plentiful lakes in rock basins. So little drift is found here, 

 and so extensive are the exposures of hare rock, that Professor X. H. Winchell has 

 called it a driftless region;* but it has been everywhere glaciated, and many de- 

 posits of subglacial till must he lodged in the depressions between hills and ridges. 

 The whole volume of drift in this region is very little, in comparison with other 

 thickly drift-covered portions of this and adjoining states, and of this little the 

 proportion which was englacial is small indeed. 



North of Rainy Lake ami the Lake of theWoods. — Continuing northward and north- 

 westward, this area of scanty drift comprises a great extent of country crossed by 

 the Canadian Pacific railway between Port Arthur and the Whiternouth river. Its 

 southwestern limit runs from Vermilion and Net lakes northward across Rainy 

 lake and northwestward across the northern, island-dotted portion of the Lake of 



the Woods. 



Dr. George M.Dawsonj and Mr. A. C. Lawsonj have referred the gravel and 

 sand beds which are widely spread southwest of this line, about the southern part 

 of the Lake of the Woods and along Rainy riverto the mouth of Rainy lake, within 

 the area of the glacial Lake Agassiz, to lacustrine action. This explanation, how- 

 ever, is inconsistent with the restriction of these deposits to a small part of the area 

 of this glacial lake, and with their extension far southward (to the head waters 

 of the Mississippi and to St. Paul, as before noted), beyond the limit of the lake 

 and upon a district that rises in part considerably above it. Instead, the distribu- 

 tion and character of these modified drift beds indicate that they were derived 

 directly from the englacial drift which abounded in the ice-sheet upon this belt. 

 On a large adjoining region next to the northeast, however, the drift is so scanty 

 that much of the surface is bare rock, strikingly contrasting with the country 

 SOUthwestward, which across distances of 100 to 200 miles is wholly drift without 

 a single rock outcrop. 



i ■■ ology of Minn., vol. i. pp. 117, 131 ; Minn. Horticultural Society, Annual Report for 1884, p. 398. 



t Report on the Geology and Resources of the region in the vicinity of the Forty-ninth Parallel. 

 1875, pp. 203-218. 



JGeol. Survey of Canada, Ann nil Report, new ~.-i ie<. vol. i. for 1885, pp. 131 and 139CC; vol. iii. for 

 1887-88, pp, 17!-17t, V. 



