hitherto observed in Greenland. 1 7 



individuals are paler and much smaller than others ; but it ap- 

 pears to me that no certain limits are to be found between these 

 varieties or races. 



107. Larus leucopteruSj Fab. 



108. ? ^Larus chalcopterus, Licht. 



Dr. Bruch (J. f. Oru. 1855, p. 282) seems to recognize this 

 species in a Gull which Holboll considers a variety of L. leuco- 

 pterus, and of which he has obtained three specimens only. I 

 myself never saw any of them. 



109. ^Larus argentatus, Briinn, 



I myself never saw more than one specimen of this species 

 obtained (viz. an adult bird in winter plumage, shot at Godt- 

 haab about ten years ago), and I have been told of only two or 

 three more sent from thence, and offered here for sale. It is 

 certainly a quite accidental and extremely rare bird in Green- 

 land. Therefore I have been somewhat surprised to learn from 

 Dr. Walker's paper that he had observed this Gull flying about 

 in the harbour of Frederikshaab. I suspect that, in the paper 

 quoted, Larus argentatus has been put down by mistake instead 

 of L. leucopterus (next to L. tridactylus, the commonest Gull in 

 Greenland), which is not mentioned by Dr. Walker, though it 

 probably did not fail in the said harbour. 



110. ^Larus affinis, Rhdt., an sp. n.? 



When I described this Gull in 1853 (/. c. p. 78), I expressly 

 observed that I did not hesitate to consider it as quite distinct 

 from Larus argentatus (the mantle being many shades darker and 

 the size smaller), but that, on the other hand, an immediate 

 comparison with Audubon's L. occidentalis (a species known to 

 me only by description) was necessary before deciding finally 

 upon its claims to be considered a new species, and that I should 

 even have referred it to the said Gull had it not been for the 

 very superior size of the latter, as given by Audubon (Orn. Biogr. 

 V. p. 320, and Syn B. N. Am. p. 328). I am still unable to solve 

 the question ; but I may be permitted to observe, that it at all 

 events appears to me a mistake, when the late Prince Bona- 

 parte, in his ' Conspectus ' (pt. 2, p. 218), refers my L. affinis to 



VOL. III. C 



