736 ABSTRACTS OF PAPERS 



Mr. Frank Le^terett called attention to the fact that in an unpublished 

 paper read before this Society in December, 1904, he had described glaciated 

 surfaces of the sort noted in Mr. Carman's paper, observed on the stones 

 imbedded in the till of drnmlins in the northern part of the southern penin- 

 sula of Michigan. These observations in the drumlins show that it is not 

 necessary that the underlying drift should become cemented or indurated 

 before such strire are produced, and that the striation may go on in the 

 course of deposition of a single drift sheet. In the locality discussed by Mr. 

 Carman there should be conclusive proof outside of the glaciation of the till 

 surface that the underlying till is markedly older than the overlying deposit. 



ON THE PRE-GLACIAL MIAMI AND KENTUCKY RIVERS 



BY N. M, FENNEMAN 



(Abstract) 



Two hypotheses are entertained concerning the regional preglacial drain- 

 age in southwestern Ohio and adjacent States : one, best stated by Prof. 

 Joseph J. James, that this drainage was southwestward along the course of 

 the present Ohio ; the other, presented bj' Mr. Girard Fowke, that the Ken- 

 tucky River flovred northeastward from its present mouth along the line of 

 the Ohio and Miami rivers, reversed, to join a great west-flowing trunk stream 

 U'hich may be regarded as an extended preglacial Kanawha. The criteria for 

 discrimination consist in (1) the depth of the rock surface along present and 

 former stream courses; (2) local differences in the width of the Ohio Valley 

 between bluffs, especially certain narrows near Cincinnati and one at Madi- 

 son, Indiana; (3) the angles at which tributaries join the present master 

 streams. From newer data on (1) it appears impossible that the drainage 

 at the time referred to could have been northward from southwestern Ohio. 

 There is no evidence of subsequent crustal warping. The rock surface de- 

 clines at least 350 feet from west central Ohio to the mouth of Kentucky 

 River, but is apparently decidedly higher below that point at Madison. Indiana. 

 It is possible that local Pleistocene changes may have made a new valley 

 there. Under (2) the chief point at issue is the narrows at Madison, which 

 are not adequately accounted for by hardness of rocks, because there are 

 other features of youthful drainage. This strengthens the supposition that 

 the preglacial Ohio made a (not yet discovered) detour around Madison. 

 The facts under (3), while not alone conclusive, favor southwestward drain- 

 age as at present (Fowke says the opposite). On the whole, the great point 

 in favor of Fowke's theory is the narrows and elevation of the rock surface 

 at Madison, but the slopes of the rock surface in western Ohio constitute an 

 insuperable objection to this theory, except by assuming notable crustal move- 

 ments of which there is no evidence. 



recent studies of the moraines of ontario and westery new york 



by frank b. tayix)r 



Discussion 



Prof. H. L. Fairchild asked if the author had determined the direction of 

 outflow of the waters drained away from the insular area or the tract of 



