18 Prof. J. Reinhardt on the Birds observed in Greenland. 
L. argentatoides, Rich, (the only race of argentatus admitted by 
him as American), this doubtful species being paler even than the 
L. argentatus proper, and consequently differing still more from 
my L. affinis. 
The specimen described in 1853, and still the only one which 
1 have seen of my L. affinis , is in the Royal Museum. 
111. Rissa tridactyla (Linn.). 
112. Pagophila eburnea (Gmel.). 
113. ? Pagophila brachytarsa (Holb.). 
Holboll established this Gull (which I have never seen) upon 
three specimens, obtained at different times, but unfortunately 
lost even before the publication of his memoir on the Avifauna 
of Greenland. Afterwards he seems to have failed in his endea¬ 
vours to get more examples, and I doubt whether any collection 
possesses an authentic or type specimen. This is much to be re¬ 
gretted. Different authors also do not quite agree in the characters 
which they ascribe to the supposed new species, and it seems to 
require further investigation before it can be finally admitted. 
Indeed, Holboll gives his Larus brachytarsus a tarsus 5 lines 
shorter than that of P. eburnea , while Brehm, who identifies 
HolbollV Gull with his P. nivea } admits only a difference of 
2 lines in the length of the tarsus (Yogelfang, p.344). Again, 
Bonaparte, who also adopts Brehm’s name, and has examined a 
specimen in the Paris Museum brought from Spitzbergen by 
Gaimard, does not mention the length of the tarsus, but makes, 
in direct opposition to Holboll, Bruch, and Brehm, the new spe¬ 
cies larger than the true P. eburnea (Consp. ii. p. 230). 
Lastly, it may be observed here, that it is a slight error of 
Bruch (in which he has been followed by Bonaparte and Brehm) 
to confine the Pagophila brachytarsa to North Greenland (Ca- 
banis* Journ. 1854, p. 108 ; 1855, p. 287); indeed, Holboll 
says positively that he obtained one of his three specimens at 
Godthaab in South Greenland. 
114. *Rhodostethia rosea (Macgill.). 
In my former lists this species is not admitted; the reason it 
is so here is, that I have been told by a trustworthy person that 
