MARYLAND GEOLOGICAL SURVEY 37 



eluded that they were Recent and gave them the name of the McIIenry 

 formation. Dr. William H. Dall confined his observations to the locality 

 at Wailes Bluff and stated that, while they have generally been referred 

 to the Pleistocene, it is probable that they will actually be found on 

 further research to be Pliocene in age. The author, who had enjoyed 

 greater opportunities for studying these clay lenses and had observed them 

 in various parts of tide-water Maryland, suggested that they all belonged 

 to one formation and thought it not unlikely that subsequent investiga- 

 tions would show that they were contemporaneous with the famous Pish 

 House clays near Philadelphia in New Jersey. Three years later in 

 1901, after further study, he concluded that all of these clay lenses be- 

 longed to one formation and were a part of the latest Pleistocene form- 

 ation, the Talbot. 



In May, 1901, while the Washington folio was still in press, the author 4 

 published a paper in which, after reviewing the work of McGee and 

 Darton on the surficial deposits of Maryland and that of Prof. R. D. 

 Salisbury in New Jerse}', he summarized the results of several years of 

 investigations. As these will be brought out later in this monograph, 

 it need only be said here that the surficial deposits were found divisible 

 into five formations which are developed as terraces lying one above the 

 other from tide level to over 500 feet, the oldest located on the highest 

 elevation. The formations and terraces were called Lafayette, Sunder- 

 land, Wicomico, Talbot, and Recent. The author further showed that 

 they were formed by the continued action of river, estuarine, and ocean 

 agencies. 



While this paper was in press Professor Salisbury and the author 

 jointly examined the Columbia deposits of Maryland and New Jersey. 

 In the following autumn (1901), the report of the State Geologist of 

 New Jersey for 1900 was issued, to which were appended a few pages 

 by Professor Salisbury on " The Surface Formations of Southern New 

 Jersey," in which a comparison was instituted between the New Jersey 

 and Maryland classifications. The views expressed in this paper were 



4 Johns Hopkins Univ. Circ. No. 152, reprinted in Amer. Geol., vol. 28, pp. 

 87-107, Aug., 1901. 



