622 LAEUS LEUCOPTERUS, WHITE-WINGED GULL. 



LARUS LEUCOPTERUS, Faber. 



White-winged Gull. 



Larus argentatus, Sabine, Linn. Trans, xii, 1818, 546. Not of authors. 



Larus arqentatus, var., Tkmm., Man. ii, 764. 



Lams hucopterus, Faber, Prod. Isl. Oru. 1822, 91.— Bp., Syn. 1828, 361; List, 1838,63.— 

 Sw. & Rich., F. B. Am. ii, 1831, 418.— Nutt., Man. ii, 1834, 305.— AuD., Orn. 

 Biog. iii, 1835, 553, pi. 282 ; Syn. 1839, 327 ; B. Am. vii, 1844, — , pi. — .— Eyt., 

 Cat. Br. B. 1836, 53.— Temm., Man. iv, 1840, 467.— Naum., V. D. x, 1840, 367, pi. 

 265.— Keys. & Blas., Wirb. Eur. 1840, 96.— Macgil., Man. ii, 1842,247.— Schl., 

 Rev. Crit. Ois. Eur. 1844, 125.— Gray, Gen. of B. iii, 1849, 654 ; List Br. B. 1863, 

 230.— Midd., Sib. Reise, ii, 1853, 242.— Lawr., B. N. A. 1858, 843; Ann. Lye. N. 

 Y. viii, 1866, 299.— Coues, Pr. Phila. Acad. 1862, 294 ; Pr. Ess. Inst, v, 1868, 

 306 ; Key, 1872, 311.— Ridgw., Ann. Lye. N. Y. s, 1874, 393 (Ohio, Wheaton).— 

 Vekr., Pr. Ess. Inst, iii, 1862, 160.— Allen, ibid, iv, 1864, 90.— Dall & B.vnn., 

 Tr. Chic. Acad. 1869, 304.— Schl., Mus. P.-B. ix, 1863, Lari, 5.— Blas., J. f. O. 

 1865, 382. 



Plautus leucopiertis, Reich. 



Glaums leucopterus, Bruch, J. f. O. 1853, 101.— Bp., Consp. ii, 1856, 217. 



Laroides leticopterus, Bruch, J. f. O. 1855, 281.— Bkehm, V. D. 1831, 745. 



Larus arcticus, Macgil., Mem. Wern. Soc. v, 268. 



tarus (jlaucoides, " Temm.''— Boie, Isis, 1822, 562.— Temm., Man. iv, 1840, 469. 



Laroides glaucoides, Brkhm, V. D. 744. 



Laru^ islandicus, Edmonst., Mem. Wern. Soc. iv, 1823, 503 ; not of Edmonst., 1822.— 

 Flem., Br. An. 1828, 139.— Jen., Man. 1835, 279. 



Laroides minor, Brehm, V. D. 1831, 736, pi. 37, f. 2. 



Laroides subleucopterus, Brehm, V. D. 746. 



Dlag. L. glaiico omnino similis, sed minor. Long. Mpedalis ; rostr. 2.00 jyoll., tars. 2.25. 

 Hah. — With the preceding. 



Adult in summer.— BWX rather small, the symphyseal eminence very largelj"^ devel- 

 oped; the depth at the angle but little more than at the nostrils. First primary 

 longest. Tarsus not longer than the middle toe and claw. Bill greenish-yellow, 

 chrome along the tomia and toward the extremity ; the tip diaphanous ; the vermilion 

 spot on the lower mandible rather small. Mantle and wings light pearl-blue, this color 

 toward the tips of the primaries, secondaries, and tertials fading insensibly into white. 

 Bases of the primaries the same color as the body of the feather ; without well-defined, 

 rounded white apices, their rhachides straw-yellow. Legs and feet flesh-colored. 



Adult in winter. — As in summer, but the head and neck narrowly streaked with 

 dusky-gray. 



Young. — "Pale, dusky cinereous, with a few slightly darker spots; the primaries 

 somewhat darker at their tips." — IBj}.'] 



Dimensions.— Length, 24 inches; wing, 16.75; bill along culmen, 1.80; along rictus, 

 2.80 ; depth at angle, 0.65 ; tarsus, 2.25 ; middle toe and claw the same. 



This species is a perfect counterpart of L.glaucus : but, although quite identical in 

 colors, may be readily distinguished by its greatly inferior size. IBeside this there are 

 some differences of proportion. The specimens before me have disproportionally weaker 

 bills than has the adult glaucus; the tarsus is not longer than the middle toe and claw, 

 and the first primary is decidedly longest. The rather larger size, darker primaries, 

 and their tliew tvell-defincd, round, ajjieal spots readily distinguish the glaucescens. 



There is a remarkable discrepancy in the statements of authors concerning the di- 

 mensions of this species. Thus, Bonaparte gives 20 inches, while Richardson says 26! 

 The specimens before me average about 24 inches, as above given. 



The discussion of the synonyms "argentatus, Sabine," and " arcticus, Macgill." is pre- 

 sented under the head of L. hutchinsii. Macgillivray's name is certainly a synonym of 

 leucoptcrus, Faber, as he himself subsequently admits; notwithstanding which, Bona- 

 parte, in his Conspectus, adopts it for what I call hutchinsii, upon what grounds does 

 not appear. Teraminck at first considered this species as a variety of the common 

 Herring Gull {L. argentatus). He subsequently, however, became convinced of his 

 error and named it L. glaucoides — an appropriate title, but antedated. In 1823 Ed- 

 monston (op. cit) applies the name islandicus to this species, only a year after he had so 

 named the L. glaucus. 



LARUS GLAUCESCENS, Licht. 

 Glaucoiis-M inged Gull. 



Larus glaucescens, Light.— Lawk., B. N. A. 1858, 842.— Coues, Pr. Phila. Acad, 1862, 

 295; Key, 1872, 311.— Coop. & Suck., N. H. Wash. Ter. 1860, 270.— Elliot, B. 



