295 



birds. M. Ailolphe Boucanl — M. Salle's correspondent — who 

 formed the present collection, has lately changed his Quarters from 

 Vera Cruz into the State of Oaxaca on tin- Pacific nde of the divi- 

 ding range. The precise localities, where he has mostly worked, are 

 La Parada, a village situated at about six leagues from Oaxaca at an 

 elevation of about 10,(K)U feet, in the cold region, and 8an Miguel de 

 las Pens, about two leagues from the same city, in the temperate 

 region. The species collected are over eiirhiy in Dumber; and though 

 there are not many of them which I consider absolutely new to science, 

 there are several birds of very great interest, and which are to he 

 seen but rarely in the Museums of Europe. Comparing this collect 

 tion with those which I have previously examined from Cordova and 

 the adjacent portion of the Atlantic slope, we notice considerable 

 differences. Taking, for example, the Wood-warblers from each, we 

 find from 



Oaxaca. 



Dendroica auduboni. 



■ nigrescens. 



toirnsendi. 



olivacea. 



Cordova. 

 Dendroica coronata. 



penrilis. 



vireiu. 



olivacea. 



This at once lets us into the secret that the western and eastern 

 species descend respectively on their own side of the continent from 

 north to south — the first three birds from Oaxaca being all Califor- 

 nian species, and those from Cordova species which are found in the 

 Eastern States ; while D. olivacea, wdiich occurs in both localities, 

 is not known to go further north than Texas, and its occurrence 

 even in that country may be considered questionable. There are 

 several other birds of different groups in this collection, such as Hel- 

 minthophaya celata,Vireo hntto/ii,C>/anocitfa califomica, &C., winch 

 are exclusively western species. Altogether there are at least ;."i 

 species in this collection which I have not met with from the lo- 

 calities on the eastern slope ; and I have thought it advisable to give 

 a list of the whole, so as to contribute something towards a knowledge 

 of the range of species. 



1. Urubitinga anthracina (Nitzsch), autea, p. 129. 

 <? juv., Parada, Oct. 1857. 



2. Accipiter FUSCUS (Gin.). 

 $ , Parada, Jan. 1858. 



3. Tinnunculus SPARVEiurs (Linn.), 

 c?, Parada, Oct. 1857. 



4. Sykmim m.iu i.n>i m (F..rt.). Cass. B. Cat. p. 184. 

 Parada, Dec. 1857. 



.-». Nyctalk lcadica (Gm.), Casein, B. CaL y. 181 

 < J, ( Unco Senores, < >ct. I B57. 



The occurrence of these two owls so far south i-. rerj in) 

 and has not hitherto, I believe, been noted. 



