be found the specimens coUected during the celebrated Exploring 

 Expeditiou of Commander Wilkes, and sorae other of the Govern- 

 ment expeditions : and, in the second place, the very extensive senes 

 of birds m the possession of the Smithsonian Institution, which 

 body now takes in charge the specimens of Natūrai History col- 

 lected by the more recent Government expeditions, as well as a large 

 mass of material received from its own numerous correspondents. 

 The United States Boundary Commission, and the six separate expe- 

 ditions for the survey of the railway route to the Pacilic, have lately 

 accumulated a very large series of specimens of birds from the 

 western portion of the continent in the hands of the Institution ; 

 and the publication of the Zoology of these expeditions (vvhich 

 Professor Baird, Mr. Cassin, and other Naturalists are now engaged 

 upon) will make very large additions to our knowledge of North 

 American Ornithology. 



Professor Baird's private coUection of birds is also very complete, 

 and contains many of Audubon's rarer types. 



The CoUege of Charleston in South Carolina possesses an inter- 

 esting collection of Natūrai History. The birds are principally 

 North American, but there are several rare species from Guba, pre- 

 sented to the College by Seiior F. A. Sauvalle of Havana. 



The following are some of the notes vvhich I took during my in- 

 spection of the coUections above mentioned, before presenting vvhich 

 I may be permitted to observe, that nothing can be more gratifying 

 than the liberal access and great facilities in every case afforded to 

 the stranger visiting the CoUections and Libraries both public and 

 private in the United States of America. 



ACCIPITRES. 



The American Vultures forming the genus Cathartes reąuire 

 further investigation before the number of the species can be satis- 

 factorily determined. Most modern vvriters now agree in separating 

 the southern red-headed and black-headed species from their north- 

 ern representatives of the United States, Cathartes aura and C. 

 atratus. Prince Bonaparte first remarked upon these differences in 

 his paper on this subject in the Comptes Rendus for 1850, p. 292. 

 But here, as also in his ' Conspectus,' he considers C. burrovianus, 

 of Cassin, the šame as the southern C. iota. This is, in my opinion, 

 certainly not the case. There are two specimens of Mr. Cassin's 

 bird in the Academy's collection from Mexico, and they most nearly 

 resemble the true aura of the States, but are at once distinguishable 

 by their diminutive size, and seem to be truly distinct from both the 

 other two red-headed species. 



Amongst the rarer types in the large series of Falconidse possessed 

 by the Academy, is the only hitherto known specimen of Cymindis 

 JVilsoni, Cassin (Journ. Ac. Phil. i. p. 21. pi. 7). This singular 

 bird is certainly quite different from Cymindis uncinata, vvith vvhich 

 Dr. Cabanis seems inclined to unite it {vide Journ. f. Orn. 1854, 

 Extra-h. p. lxxx); and I have lately been informed that Dr. Guud- 



