488 PROCEEDINGS OF BALTIMORE MEETING. .: 



clay-loam in the viGinity of Trenton, extensively used for brick, has been regarded 

 as typical Columbia. This clay-loam belongs to the Jamesburg formation. The 

 Pensauken formation underlies it unconformably. To the north the Pensaukenis 

 overlain by the extreme edge of the oldest glacial drift, a little north of Somerville, 

 but there are not sufficient data at hand for determining the length of the interval 

 between them. The relations between the two certainly seem to permit the sug- 

 gestion that the Pensauken may correspond with the Lafayette formation of the 

 south, though this is confessedly uncertain. On the other hand, the occasional 

 bowlders in the Pensauken seem to suggest that ice may have been concerned in 

 their transportation. The oldest glacial drift which has been recognized overlies 

 the Pensauken near Raritan and Somerville and seems to be older than the James- 

 burg, although the striated bowlders in this formation clearly indicate that it was 

 made during or after the beginning of the ice period. If the Jamesburg beds do not 

 represent the extra-glacial equivalent of the first glacial epoch, there would seem to 

 be no such representative unless it be the Pensauken. If the Pensauken beds be 

 Pleistocene, there is no stratigraphic or geographic reason why the Beacon Hill 

 gravel may not be Lafayette. At present, nothing seems certain beyond this : The 

 Jamesburg and all later formations are surely Pleistocene. The Pensauken may be 

 Pleistocene or it may be pre-Pleistocene. If the former, the Beacon Hill gravel may 

 be Lafa3'^ette or anything older back to Miocene, so far as stratigraphic and geo- 

 graphic relations are concerned. If the latter, the Beacon Hill gravel might still 

 be either early Pliocene or Miocene. 



In the absence of the author, the following paper, which was pre- 

 sented to the Society through Professor W. H. Hobbs, was read in 

 abstract by J. P. Iddings : 



ON THE qUARTZ-KERATOPHYRE AND ITS ASSOCIATED ROCKS OF THE BARABOO 



BLUFFS, WISCONSIN 



BY SAMUEL WEIDMAN 



This paper is published in the science series of the Bulletin of the 

 University of Wisconsin, volume i, number 2, pages 35-56, plates 1-3. 



The author of the next paper was absent, and it was read by E. O. 

 Hovey : 



ON NEW FORMS OF MARINE ALGjE FROM THE TRENTON LIMESTONE, WITH 

 OBSERVATIONS ON BUTHOGRAPTUS LAXUS, HALL 



BY K. P. WHITFIELD 



Remarks were made upon the matter of the paper by H. M. Ami. The 

 paper is published in the Bulletin of the American Museum of Natural 

 History. 



