THE PLAINS AND COLORADO 129 



life of Princeton in the years from 1875 to 1881, 

 and to compare them with those of to-day. 



Most of us are aware that the fauna and flora 

 of a given region is liable to slow and gradual 

 change. Perhaps few of us realize how rapid and 

 radical such development may become. Some- 

 times this is effected by the adventitious aid of 

 man, a good example of which is the introduc- 

 tion of the English sparrow into North America. 

 More recently the starling has been naturalized, 

 and has become plentiful in the immediate vicinity 

 of New York City as a wild bird. 



The stories of our earlier observers dwell upon 

 the abundance of the wild turkey throughout all 

 eastern North America, and of the heath-hen at 

 various points in the same region. Except in 

 remote and unsettled districts the wild turkey has 

 disappeared as a part of bird life, and the heath- 

 hen exists only in limited numbers on the island 

 of Martha's Vineyard. These are examples of the 

 kind of change indicated. 



I have spoken of the wild pigeons that bred in 

 the vicinity of Mount Auburn Cemetery in Cam- 

 bridge during my college days. One of the nota- 

 ble features of bird life in the vicinity of Princeton 

 which attracted my attention were the spring and 

 fall flights of the passenger-pigeon. Very con- 

 siderable colonies also nested in the woods along 

 the ridge known as Rocky Hill. In those days 



