622 THE JOURNAL OF GEOLOGY. 



light-colored sandstones that lie below the alternating series into 

 the middle rather than the upper division. 



Professor Van Hise gave a lucid sketch of the succession of 

 deposits in the Marquette district and the grounds on which his 

 interpretation is based. The paper showed the steady progress 

 that is being made in the disentanglement of the gnarled structure 

 of that region. 



The papers of the Professors Wright awakened special interest 

 from their relation to previously controverted ground. Contrary 

 to their recent contention, they now extend the glaciated area 

 so as to include the localities of High Bridge and Pattenburg and 

 a considerable territory in the Triasic region essentially as main- 

 tained by Professor Salisbury before the Professors Wright took up 

 the special study of the matter, though this was not as distinctly 

 acknowledged as might have been desired. The discussion on 

 the part of Chamberlin and McGee took the congratulatory form 

 in view of the removal of one important point of difference and 

 the advance toward harmonious views. It was noted that the 

 points of difference were essentially reduced to two : The corre- 

 lation of the Trenton gravels and the age of the extra-morainic 

 drift relative to the moraine. In regard to this last it was pointed 

 out that an important contribution had been made, unwittingly 

 perhaps, to the presumption of great difference in the ages of the 

 two drifts, in the fact that the outer drift, especiallv at such local- 

 ities as High Bridge and Pattenburg, where it is thick, could not 

 be presumed to be of the same age and character as that of the 

 moraine and moraine-bordered drift, or its glacial origin would 

 not have been previouslv denied by the Messrs. Wright, and that 

 its age must be presumed to be very much greater or it could not 

 have been referred to a residuary origin, especially to residuary 

 derivation from formations which have disappeared from the 

 neighborhood, since the moraine and moraine-bordered till are 

 very distinctly characterized glacial formations of fresh aspect, 

 while residuary accumulations and residuary topography are inher- 

 ently expressions of age. 



Dr. Spencer submitted a large mass of valuable data relative 



