48 INTRODUCTION. 



their summer abodes, the desolate regions of Greenland and 

 Spitzbergen, to the fens and sea-shores of the West India islands 

 and South America, the usual places of their winter retreat, 

 while those of the Purple Martin and common Swallow still 

 remain, in vulgar belief, wrapt up in all the darkness of mys- 

 tery. 



Philadelphia, March 1st, 1819. 



