294 PROCEEDINGS OF THE ACADEMY OF 



1. Lakus Hutchinsii Richardson. 



?L. glacialis, Benicken (nee Macgill. qui L. glaucus, Brumi.) Glaucus 

 glac. Bruch, 1853. Laroides glac. Bruch, 1855. Leucus arcticus, "Macg." 

 Bp. 1856, excl. synon. (nee Macg.) Larus Hutchinsii, Richardson, F. 

 B. A. 1831, ii. 419. 



Sp. char. Adult: Bill flesh-colored at hase, blackish on terminal third. 

 Entire plumage pure white, the shafts of the feathers straw yellow. Feet 

 light flesh-color. Young : Head, neck and upper parts mottled with light 

 reddish brown, appearing on the latter as irregular patches, and on the rump 

 as more or less obsolete transverse bars. Under parts a nearly uniform very 

 light reddish brown, the under tail coverts transversely barred with white. 

 Wings and tail pure white. Length 27=> inches ; extent 60 ; wing 17| ; bill 

 above 2*40 ; along gape 3*20. Tarsus 3 - 40 ; middle toe and claw 3*50. 



Hob. Arctic America ; North Pacific ; New York State ! 



The name "Arcticus Macgill." is usually applied to this bird. Bonaparte 

 adopts the name in his Conspectus, moreover, considering it identical with 

 L. argentatus of Sabine's Memoir on the Birds of Greenland. But both these 

 authors speak of a notable amount of blue on the back, ( ' 'back pure pearl gray, 

 with a good deal of blue" " crerulescente-perlaceo.") Moreover, Macgilli- 

 vray himself subsequently says that his arcticus is the leucopterus Faber. I 

 have not been able to find the original description of glacialis of Benicken ; 

 but Bruch, who adopts that name, speaks of the "gull-blue" of the upper 

 parts. In the Fauna Boreali-Americana, ii. p. 419, there is given a brief de- 

 scription of a Gull, which is certainly, I think, the present species. The 

 names " arcticus" and "glacialis" being in my opinion untenable, I adopt 

 that of Hutchinsii, proposed by Richardson. I have no doubt of the validity 

 of the species. 



This species is now introduced into the Fauna of the United States through 

 a specimen killed in Washington co., New York, and presented to the Smith- 

 sonian Institution by Mr. Peter Reid. It was killed in midwinter, while feed- 

 ing on a dead sheep. Other specimens were collected by Mr. Stimpson in 

 Behring's Straits, while connected with the North Pacific Expedition under 

 Capt. Rodgers, U. S. N. 



b. Color above very light pearl blue. Primaries like the back, fading 

 insensibly into white at some distance from the tips. 



2. Larus glaucus Briinnich. 



Larus glaucus, Brunn. 1764 et auct. Laroides glauc. Bruch, 1855. Leucus 

 glauc. Bp. 1856. Plantus glauc. Reich. 1853. Larus consul, Boil, 1822. 

 Glaucus cons. Bruch, 1853. Larus islandicus, Edmonston, 1822, nee 

 Edm. 1823. Larus glacialis, Macgill. 1824; (nee Benick.) Larus 

 leuceretes, Schlelp. L. leucopterus, Vieill. L. giganteus, Benick. fide Bp. 



Sp. char. Length 29 inches ; extent 62 ; wing 18-5. Bill above 2-75, along 

 gape 3-75 ; height at nostril -80, at angle -85. Tarsus 3"00 ; middle toe and 

 claw 2*75. (Dimensions sufficient to separate it from leucopterus, the only 

 other N. A. species in this group, (6.) 



Hal>. Arctic seas, coming southward in winter. Labrador in summer. 



',*>. Larus leucopterus Faber. 



L. argentatus, Sub. 1818 ; nee Briinu., nee auct. L. argentatus, var. Temm. 

 L. arcticus, Macgill. ; (nee Leucus arct. "Macg." Bp. 1856.) Larva 

 leucopterus, Faber; (nee Vieill., qui L. glaucus, Briinn.) Laroides 

 leucop. Bruch, 1855. Glaucus leucop. Bruch, 1853. Leucus leucop. Bp. 

 1856. Plantus leucop. Reich. Larus isla>idicus, Edmonst. 1823, nee 

 1822. Larus glaucoidcs, Temm. 1840. Laroides glaucoides et leucop- 

 terus, Brehm, fide Bp. 



[June, 



