1 86 EXTINCT MONSTERS 



When I add that some of the most interesting discoveries were 

 made in the hunting-grounds of the hostile Sioux Indians, who 

 regard such explorations with superstitious dread, you will under- 

 stand another phase of the problem. I might speak of even 

 greater difficulties and dangers, but the results attained repay all 

 past efforts, and I hope at no distant day to have something 

 more of interest to lay before you." 1 



1 American Journal of Science, vol. xli. p. 17G. 



