1886.] NEW YOKE ACADEMY OF SCIENCES. 59 



merit of the question, and of the need of a larger income, with 

 a request for the individual opinion of the members. 



Mr. H. T. Woodman announced the discovery of an ele- 

 phant's tooth, probably Elephas Americanus, in the beds of 

 silicified coral in Florida. The President described the char- 

 acter, range, etc., of Elephas and Mastodon. 



Mr. F. J. H. Merrill read the following 



NOTE ON THE GREEN POND MOUNTAIN GROUP OF NEW 



JERSEY. 



The Green Pond Mountain series of rocks in northeastern 

 New Jersey, which also extends through Orange County, New 

 York, to the Hudson Eiver and for some distance beyond, has 

 heretofore been studied by geologists, since the time of Professor 

 Henry D. Rogers, without positive determination of its age. 

 Rogers believed the red conglomerate and sandstone which 

 forms the base of the series, to be Triassic, and Mather surmised, 

 that it might be Oneida, while in the report of the Geological 

 Survey of New Jersey for 1868, it was described as Potsdam. 

 Recent investigations by the State Geological Survey have dis- 

 covered evidence which fixes the horizon of the system. 



Dr. N. L. Britton has found that a fosslliferous limestone, 

 formerly described as Trenton, is Lower Helderberg, and the 

 speaker has discovered Oriskany and Corniferous fossils in a 

 coarse white sandstone and conglomerate; so that there is repre- 

 sented a continuous series of rocks from the red conglomerate, 

 which is of Oneida age, and rests unconformably on the magne- 

 sian limestone in places, to certain blue slates and grits which 

 contain fossils, probably of Hamilton age, and which in New 

 York State have yielded Psilophyion princeps, Dawson, and 

 other Devonian plants. The slates in the valley southwest of 

 Greenwood Lake, which were formerly supposed to be of Hudson 

 River age, are proved stratigraphically and palasontologically to 

 belong to the Upper Devonian. (See Annual Report Geol. 

 Survey of N. J., 1886). 



Mr. L. E. Chittenden spoke as follows upon 



