PREFACE. 



Perhaps I cannot better express my deep sense of the generosity with which my labors 

 in America have been supported, than by a simple narrative of the manner in which I 

 have collected the materials for the series, of which this volume is the first, and of the 

 growth and progress of the plan for its publication. 



Since the time of my arrival in this country, now eleven years ago, 1 have lost no 

 opportunity of making collections wherever my lecturing excursions led me ; and, by my 

 own efforts, and by the friendly aid of persons throughout the United States, who have 

 shown from the beginning a warm interest in my scientific pursuits, I have succeeded in 

 bringing together an extensive museum of purely American specimens. My opportunities 

 for investigation were, of course, daily increased, and at the end of eight or nine years 

 I had on hand a great quantity of materials, containing the results of my studies in 

 this country; but the expense attending the collection and support of so large a museum 

 more than exhausted the means which I was able to devote to it, and I felt obliged to 

 renounce all idea of publishing the results of my labors. I had them in tangible form, 

 not with any expectation of ever seeing them in print, but in the hope that after my 

 death my collections and papers would be found a useful guide for others, and might be, 

 in the end, of some service to science in America. 



It is now two years since, in conversation with Mr. Francis C. Gray, of Boston, — now 

 no longer living to see the result of his disinterested and generous efforts in behalf of 

 science, — I mentioned to him the numerous preparations which I had made to illustrate 

 the Natural History of North America, and my regret that tlie costliness of such works 

 must prevent the publication of the materials I had collected. He entered at once into 

 tlic matter with an energy and hopefulness which were most inspiring: spent some time in 

 examining my manuscripts; and, having satisfied himself of the feasibility of their publica- 

 tion, set on foot a subscription, of which he took the whole direction himsell", awakening 

 attention to it l)y persona! a|)plication to his friends and acquaintances, by his own lib- 



