PREFACE TO VOLS. II. A NL» III. 147 



others established by Vieillot, of whose existence as distinct species 

 there can hardly be any reasonable doubt. In order more clearly to 

 explain our meaning, it may be proper to enter into the following 

 calculations. 



In Linnd's last edition of his Systema Naturw, a work professing to 

 contain, like all others, all the then known birds of the United States, 

 which had been chiefly taken from the original sources of Catesby and 

 Edwards, only one hundred and eighty-three are assigned to North 

 America. It is true that he was acquainted with several other North 

 American birds which also inhabit other countries, those common to 

 Europe especially ; but as many of the one hundred and eighty-three 

 are merely nominal, we may allow them to counterbalance those omitted. 

 Of the entire number, one hundred and three are land birds, all which 

 we have verified either as real or nominal, four excepted, of which Picus 

 hirundinaceus alone (a real species) may have escaped Wilson and our- 

 selves, though we do not believe it. Of the three remaining, two, La- 

 niits canadensis and Loxia canadensis, are now well known to be South 

 American birds given as North American through mistake ; and the 

 third, Sylvia trocMlus of Europe, may have been reckoned as American 

 on account of the resemblance between it and the female of some 

 American Warbler, probably Sylvia trichas. 



Since the time of Linn^ however, great attention has been paid to 

 American Ornithology, and very numerous contributions made to the 

 Fauna of the United States, particularly in the standard works of Pen- 

 nant and Latham. As all these are embodied in Latham's vast compi- 

 lation, the Index Ornitliologicus, we shall take that as our guide. We 

 there find that no less than four hundred and sixty-four species are 

 set down as North American ! It is hardly necessary to remark how 

 greatly surcharged with nominal species this number must be, when 

 we consider that after the lapse of many years, and the addition of 

 so many genuine species by Wilson and ourselves, the number wo 

 admit is still short of four hundred. A work professing to review with 

 care the North American part of Latham's Index, species by species, 

 on the plan of our " Observations on the Nomenclature of Wilson's 

 Ornithology," is still a desideratum ; and if executed with accuracy and 

 judgment, would be as advantageous to science, as arduous for the 

 naturalist who should undertake it. For the present, leaving what wo 

 have to say concerning the water birds to the volume wherein they 



