INTRODUCTION. 



The primary object in undertaking the present work was to 

 furnish a list of American Birds in the Museum of the Smithsonian 

 Institution, with their localities and donors; and, as many of them 

 are of considerable rarity, and others new to science, the opportu- 

 nity has been embraced to give synoptical tables and descriptions 

 of some of the genera and species. The signatures were distributed, 

 as printed, to the leading ornithologists of the day, beginning June, 

 1864, and ending June, 1866; and the "Review" has been exten- 

 sively quoted by writers. 



It was at first proposed to confine the "Review" to North^ and 

 Middle America, but gradually the plan was extended until, in the 

 later monographs, all procurable American species were included. 



The present part of the "Review" includes ajl the slender-billed 

 Oscines, with the exception of the Cserehidse, which would have 

 been added but for the diflBculty of presenting a satisfactory defi- 

 nition of the genera, as compared with the allied forms. 



A second part of the "Review" will be published as soon as it 

 can be prepared. 



SPENCER F. BAIRD, 



Assistant Secretary S. I. 



Smithsonian Institution, 

 November 20, 1872. 



' The southern boundary of the United States, bnt also including the 

 whole Peninsula of Lower California, is here taken as that of North America ; 

 while by Middle America is to be understood the region intervening between 

 the United States and the southern end of the Isthmus of Darien, and em- 

 bracing the whole West Indies, excepting Tobago and Trinidad. 



(iii) 



