hitherto observed in Greenland . 
17 
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 leucqpterus, Fab. 
108. ? *Larus chalcopterus , Licht. 
Dr. Bruch (J. f„ Orn. 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 f Conspectus’ (pt. 2. p. 218), refers my L. affinis to 
vol. hi. c 
