Abbott.] 102 [October 18, 



of the one fossil as such, not applicable to the other. The 

 same agency that brought the one from the upper valley of the 

 Delaware, brought the other, and after long years, they come 

 again to light, and jointly testify, that in that undetermined long 

 ago, the creatures to which they respectively belonged, were liv- 

 ing together, in the valley of the river. 



In one respect, these two fossils do differ, and perhaps the 

 variation possesses some significance. The mastodon tusk has not 

 been subjected to any protracted exposure to running water, or 

 sand and water. It is not, in this respect, like the water-worn 

 pebbles of the gravel deposit, as is true of the tooth. It has, 

 without doubt, been subjected to a prolonged exposure to every 

 agency that goes to make a pebble from a fragment of rock, and 

 therefore suggests the possibility that it was a veritable fossil 

 prior to the floods that brought it finally to its place in the Tren- 

 ton gravels. We will give the benefit of the doubt, however, in 

 favor of those who advocate man's recent origin, and still there 

 remains the indisputable fact, that remains of the mastodon and 

 man have been found associated in no uncertain way. 



In a recent article on early man in America, in Harper's Maga- 

 zine, I find it stated that the further study of Trenton gravels 

 " may yet conclusively establish the fact that the aboriginal 

 American man was contemporary with the mammoth " — but adds 

 " must we not admit that in our efforts to explain the origin of 

 the first American man, it is necessary, after all, to end with an 

 interrogation mark?" 



The secret of man's origin in America may never be revealed 

 — but these gravels lie upon the outskirts of that origin ; and I 

 point to these implements and this tooth and claim that we can 

 assert the contemporaneity of the mastodon and man, and end 

 the sentence with a triumphant exclamation mark ! 



In conclusion, I desire briefly to call attention to another phase 

 of the archaeology of the Delaware Valley, which is well worthy 

 of attention. 



As has been mentioned frequently, the typical palaeolithic 

 implement is made of argillite. Were no other stone implements 

 found in this locality, of this mineral, the evidence would be even 

 stronger than it now is, that they mark a remote and distinct 

 phase of humanity in this region ; but other objects of argillite 



