12 EXTINCT TYPE OF DOG. 



For many years I hnxe been carefully observing our American cavernous 

 districts, Avith a view to determining the points most likely to aflford good 

 places for exjiloration. I am inclined to believe that the caves of this 

 district are more likely to furnish important paleontological data than 

 those of any other region known to me. The reasons for this belief are 

 as follows : 



In the first place, the very extensive caves in the Subcarboniferous 

 escarijment are peculiarly well fitted for the use of the primitive races 

 of men who may have inhabited this country. They are well placed for 

 the purposes of refuge, being easily defensible, and abounding in Avater. 

 The region near these springs was rich in game and fish, and well fitted 

 for agriculture. It still abounds in the remains of its aboriginal peoples. 

 If our American caves were ever extensively used by the primitive peo- 

 ples of the country, evidence of such occupation will surely be found here. 



The caves in the Cambro-Silurian sei'ies, on which the Ely cave lies, are 

 not so well placed for human use as those in the Subcarboniferous escarp- 

 ment, yet, as we have seen, they are found under conditions that favor 

 their preservation for far longer periods of time. They are often found 

 under conditions such as to make it certain of their having come down 

 from times so remote that we may fairly hope to find within them fossils 

 of the Pliocene age. All this region abounds in this class of caves, and 

 among them are many which, occupying the hill-tops at points of several 

 hundred feet above the present level of the streams, are certainly far 

 more ancient than the beginning of the last glacial period. 



This valley of the upper Tennessee lies in the southernmost part of the 

 region that was occupied by the glaciers of the last ice time. The edge 

 of the great ice-field came down to near the Ohio in the country one hun- 

 dred miles to the north, and local glaciers occupied the higher districts in 

 the North Carolina Mountains, hills that are within sight of this valley. 

 Here must have flourished the remarkable fauna that occupied the regions 

 near this ice sheet, and here, if anywhere, we may hope to find the remains 

 of man associated with extinct groups of animals. 



The great extent of this cavernous district is also a very advantageous 

 feature for the naturalist's work. Between the head waters of the Tennes- 

 see river system in southwestern Virginia and the neighborhood of Chat- 

 tanooga, over an east and west Avidth of abt)ut sixty miles, there are some 

 thousands of these caverns; so that the ex])lorer will have an abundant 



