328 MR. H. SAtJNDERS ON THE STERCORARIIN^. [Mar. 21, 



only those of the first and second primaries are white, those of the 

 third and successive primaries heing dark. I am indebted to Mr. 

 R. CoUett, of Christiania, for pointing out to me, some years since, 

 this excellent distinction. The L. parasiticus of Linnaeus is there- 

 fore not S. crejndatus, but the "Buffon's Skua;" and so is, 

 according to my view, Catharacta parasiticus of Briinnich ; but 

 it is needless to discuss the latter name, as it is out of date. 



Dr. Coues considers that the Larus crepidatus of Gmelin is 

 in all probability based upon the young of the Pomatorhine Skua, 

 to wliich Brisson gave the name of Stercorarius striatus. It is true 

 that Gmelin (who translated from Latham) identifies S. striatus of 

 Brisson with his L. crepidatus ; but although S. striatus is certainly 

 a young Pomatorhine, it was by no means easily recognizable by 

 the naturalists of that day ; and, moreover, Gmelin correctly cites 

 in the first ])lace Catharacta cepphus, Briinn., which is certainly this 

 species, and in the third line refers to " Le Labbe ou Stercoraire " of 

 BiiflFon, whose figure ('Planches Eulumine'es,' No. 991) is an ex- 

 cellent one, besides giving an accurate description of the tail-feathers 

 (" rectiicibus duabus intermediis longoribus ") ; he also refers it to the 

 "Black-toed GuU" of the 'Brit. Zool.,' which is clearly this species. 

 This would be quite sufficient to impose Gmelin's name of jL. crepidatus 

 upon "Richardson's Skua;" but the name did not actually originate 

 with Gmelin. On referring to Hawkesworth's ' Voyages ' ( 1 773), vol. 

 ii. p. 15 (not vol. i. p. 15, as erroneously cited by Latham, and of 

 course duly copied by Gmelin, without reference), we find in the 

 narrative of Lieut. Cook's voyage in the 'Endeavour' that "on the 

 8th October 1768 (when a little to the south of the Cape-Verd 

 Islands) Mr. Banks [afterwards Sir Joseph Banks] shot the Black- 

 toed Gull not yet described according to Linnseus's system ; he gave 

 it the name of Lai-us crepidatus.'" The Black-toed Gull is described 

 in Pennant's 'British Zoology,' vol. ii. p. 419 (1768); and plate 2 

 is an excellent representation of a "Richardson's Skua" of the 

 year, the feet of this species at that age having the upper part of the 

 webs yellowish, and the posterior portion black, giving the bird the 

 appearance of being " shod" or " sandalled," whence Banks's some- 

 what quaint Latin rendering. I think it probable that the bird was 

 identified from Pennant's description and figure ; for in the MS. in 

 the British Museum of Solander, who was also in the ' Endeavour,' 

 there is indirect evidence of that work having been on board ; but 

 as Banks gave no description, it is perhaps safest to cite Gmelin as 

 the authority for the name. 



It is now well known that there are two very distinct plumages to be 

 found in birds of this species, even in the same breeding-places — an 

 entirely sooty form, and one with hght underparts,— and that white- 

 breasted birds pair with whole-coloured birds as well as with those 

 of their respective varieties. If this species is "dimorphic," the 

 offspring of one particoloured and one whole-coloured bird ought to 

 resemble one or other of their parents without reference to sex ; my 

 examination of upwards of a hundred specimens from widely different 

 localities and in all stages inclines me to (he belief that this is not 

 the case, and that the young of such union will be intermediate, 



