1896.] Anthropology. 257 



ture layer, our digging had fairly proved at Oxkintok, Loltun and 

 Sabaka, and though we had often failed to reach rock bottom at other 

 caverns, there was nowhere ground for supposing that deeper digging 

 or blasting would have upset our inference. An earlier people visit- 

 ing Yucatan under its present topographical conditions must needs 

 have left their trace in the caves, and because the undisturbed earth 

 beneath the culture layer discovered, always failed to show trace of any 

 deeper, older or more primitive human visitor, the conclusion was that 

 no such earlier people had seen the region while its stony hills, its tor- 

 rid plain, and its damp caves were as they now are." 



The evidence secured by Mr. Mercer justifies this conclusion so far 

 as it goes. To prove that a human population existed in Yucatan 

 prior to that whose remains were actually found, it will be necessary 

 to discover another series of deposits inside or out of an older type of 

 caves. No such caves were found, and while it cannot be asserted that 

 such will not be found, it is evident that they must be very rare if 

 existing in the region explored. The case of Yucatan may prove to 

 be similar to that of the United States, where I have shown on paleon- 

 tologic grounds, 3 that cave deposits of two different ages exist. .The 

 remains of vertebrate life found in the caves of Yucatan explored by 

 Mr. Mercer, are those of the existing fauna of the country, and the de- 

 posits correspond, therefore, with those of the second (postchamplain) 

 age of the northern caves. Caves of prechamplain age are rare in the 

 United States, as shown by Mr. Mercer's earlier researches, having 

 been probably removed by the action of water during the Champlain 

 submergence. That such a submergence may have also taken place 

 in Yucatan is indicated by the recent researches of Spencer ; but if so, 

 a cleaner sweep of them was made than was the case in North Amer- 



Among the remains of animals which were discovered, those of the 

 horse occurred in two caves, and the dog in one. It is probable they 

 both belong to the domesticated species. 



I append some examples of the very admirable illustrations with 

 which the book abounds. 



Apart from its scientific value, this book will interest the general 

 reader for various reasons. It is written in a pleasant style, and many 

 side lights are thrown on the characters of the country and people. 

 That the exploration was not without the element of danger is shown 

 by the tragic death of one of the natives ; while the sufferings of the 

 3 American Naturalist, 1895, p. 598. 



