Natttral Sciences of Philmlelphia during the Year 1824. 349 



Petrels, which had not been clearly understood by former 

 writers. He proves that there are four distinct species, three 

 of which had been established by Temminck, whose names 

 he of course retains ; the fourth species, which our author 

 admits, appears to be the same which Wilson had described 

 as the Procellaria j^elagica : it is an inhabitant of North Ame- 

 rica, but is seen at a considerable distance from our continent, 

 as is proved by the fact of our author's having killed an indi- 

 vidual of it near the Azores. This species being distinct from 

 the pelagica of European writers, as well as from the other 

 species of this genus, our author has applied to it " the name 

 of JVilsonii, as a small testimony of respect to the memory of 

 the author of the American Ornithology, whose loss science 

 and America will long deplore." This species, besides its 

 other distinctive characters, is easily recognised at first sight 

 from its congeners by a yellow spot upon the membrane of 

 the feet, a character which Mr. Bonaparte considers as per- 

 manent even in dried specimens. 



Wilson had, in the eighth volume of his valuable work, de- 

 scribed as the Anasfuligula of European authors a bird which 

 appears to be distinct, and as yet unknown to European orni- 

 thologists. It ranges over the whole continent of North Ame- 

 rica, having been seen by Lewis and Clarke on Columbia river, 

 by Mr. Say on the Missouri, and being occasionally met with 

 in the Philadelphia market. Mr. Bonaparte describes it under 

 the name of A. nifitorques. The crest of the ftiligida offers its 

 principal distinctive character, being very evident in this bird, 

 while in the nifitorques it scarcely exists. The fine chesnut 

 collar, the pied bill, and the beautiful lineations of the sides, 

 are also distinctive characters of the male nifitorques. An im- 

 portant and constant distinction between the two birds, with- 

 out reference to variations of sex or age, is the spectdum, which 

 in thej'tiligu/a is permanently white, while in the nifitorques it 

 is invariably ash- coloured. 



Mr. Bonaparte's principal memoir is undoubtedly that which 

 has for its object to establish a concordance between the no- 

 menclature used by Wilson and that of European ornitholo- 

 gists. This was a delicate and arduous task, of which a con- 

 siderable part has been achieved. W'e shall refrain from any 

 observations upon the results which Mr. Bonaparte has pre- 

 sented to the Academy, as these may be more advantageously 

 considered alter his task sh«ll have been comjileted. In the 

 uican while, the following cjuotation from his preliminary ob- 

 servations will show that in undertaking this task no dispa- 

 ragement of WiUon's talents or labour was intended : " Wil- 

 son, though one of the most accurate of oiiiithologists, one 



who 



