G. F. Eaton— Prehistoric Fauna, of Block Island. 151 



rence of the modern Chelonidae can be applied equally well to 

 those of prehistoric times. Similar problems of distribution 

 arise in the case of the land mammals represented in the shell- 

 heap collections. Like the reptiles, they may possibly have 

 been transported by natural or human agency, or some of them 

 may have traveled there on the ice just before the final retreat 

 of the great glacier ; but their occurrence may be explained in 

 a simpler and more satisfactory way which will not antagonize 

 the accepted theories concerning the recent geology of the 

 New England coast and the distribution of its fauna. In order 

 to do this, it will be necessary to ascertain what surface condi- 

 tions prevailed on the Island until about two hundred and 

 fifty years ago, and also to consider some evidences of change 

 in level during the recent period. 



Mr. Livermore's " History of Block Island " contains an 

 interesting chapter on " Peat and Timber," giving many valu- 

 able references to the forest trees of the Island. Mr. Liver- 

 more writes that " a heavy growth of timber covered much of 

 the surface of the Island at the time of its settlement ; " and 

 that "the kinds of timber most common here were oak, elm, 

 pine, hickory, ash and cedar, with'a thick growth of alders in 

 swampy places, which were small and numerous." In regard 

 to the peat deposits the same author states that " the beds are 

 also numerous, and in every part of the Island. Some cover 

 several acres, and others are much smaller. Some are shallow, 

 and others are deep, and most of them were formed by vege- 

 table matter, leaves, bark, nuts, grass, ferns, decayed wood, 

 etc., that for ages had been washed down . the surrounding 

 steep little hillsides. Thus peat beds were deposited upon 

 some of the highest parts of the Island, as upon Clay Head, 

 and the supply was ample, if not exhaustless." Mr. Livermore 

 makes this statement also : " In the peat deposits roots and 

 trunks of large trees are frequently discovered." 



From the foregoing quotations, it is evident that, long 

 before the Island was discovered by Europeans, it bore a rich 

 growth of those species of forest trees which are now found 

 on the mainland ; and the peat deposits imply the former 

 existence of many ponds and swamps scattered over its forest- 

 clad surface. With the destruction of the trees and the con- 

 stant diminution of the Island itself, owing to the erosion of 

 its shore, the number and size of the fresh-water ponds have 

 become less, and consequently many of the springs on the hill- 

 sides have failed. Still, even now, the supply of water would 

 be sufficient for the support of many kinds of wild animals. 



Evidence of the old Connecticut River channel between 

 Block Island and Montauk Point has been already referred to 

 in this paper. Attention is now called to the fact, obvious 



