LARUS. 419 
N. Amer. Birds, 2nd ed. p. 21°; Saunders, Cat. Birds Brit. Mus. xxv. p. 1857; Oates, 
Cat. Eges Brit. Mus. i. p. 205°. 
Pil. estiv. Supra margaritaceo-cinereus ; tectricibus alarum et secundariis intimis dorso concoloribus, his 
exterioribus nigro terminatis; ala spuria et tectricibus primariorum pure albis; primariis albis, nigro 
terminatis, interioribus cinereis, intimis cinereis, secundariis concoloribus ; uropygio et cauda pure albis ; 
pileo, facie laterali et gutture toto plumbescenti-nigris ; collo postico et laterali, et corpore subtus reliquo, 
cum subalaribus et remigibus intus pure albis: rostro nigro; pedibus late aurantiaco-rubris, unguibus 
nigris; palpebris aurantiacis; iride saturate brunnea. Long. tota circa 13:5, ale 10-4, caude 3:9, 
culm. 1°3, tarsi 1°45. 
9 haud a mari distinguendus. Long. tota circa 12°5, ale 10-0. (Descr. maris et femine ex Washington, D.C. 
_ Mus. nostr.) 
Ptil. hiem. ptilosi estive similis, sed pileo nigro, postice et regione auriculari postica nigro notatis ; pedibus 
carneis. a 
Juv. ptilosi hiemali similis, sed pileo fuscescenti-brunneo, plumis omnibus albido terminatis et subterminaliter 
brunnescentibus; cauda nigro terminata distinguendus. (Descr. Q juv. ex Ipswich, Mass. Mus. 
nostr.) 
Hab. Nortu Amunrica generally, breeding mostly north of the United States °—Mexico, 
Mazatlan (Grayson 3), Guanajuato, Guadalajara (Dugés 7), Jalisco (Sanchez *). 
Bonaparte’s Gull is a well-known inhabitant of North America, migrating south 
in winter along both coasts. At this season of the year it also visits Mexico; but the 
species must be somewhat uncommon, as, beyond the localities recorded by Dugés? 
and Sanchez 4, it has been met with only at Mazatlan. Grayson® states that a few 
individuals were seen here, and some procured, in a freshwater lagoon near the sea- 
shore, on the 27th of March, 1868, but he never saw one subsequently °. 
The flight of this Gull is said to be graceful and light, resembling that of a 
Tern. ‘The bird passes through the interior of North America to its breeding-grounds. 
MacFarlane observed its nests in the region of Fort Anderson, these being placed in 
bushes or trees at a height of from four to twenty feet from the ground; one was 
composed of dark velvety pine-leaves and down, while others were of sticks lined with 
hay or some soft substance. Richardson and also Kennicott met with it nesting on 
pine-trees °. | 
The eggs, which are usually three, rarely four, in number, are olive-buff, with light 
or dark brown markings and underlying rather indistinct purplish spots, these being 
small and having a tendency to form an irregular and ill-defined zone round the 
larger end 8. 
2. Larus franklini. 
Larus franklini, Swains. & Richards. Faun. Bor.-Amer., Birds, p. 424, t. 71°; Scl. & Salv. P. Z.S8. 
1871, p.577°; Baird, Brewer, & Ridgway, Water-Birds N. Amer. ii. p. 258°; Ferrari-Perez, 
Pr. U.S. Nat. Mus. ix. p.179*; A. O. U. Check-l. N. Amer. Birds, 2nd ed. p. 20°; 
Saunders, Cat. Birds Brit. Mus. xxv. p. 191°; Oates, Cat. Eggs Brit, Mus. i. p. 206’. 
Chroicocephalus franklinii, Lawr. Mem. Bost. Soc. N. H. i. p. 317 * 
Larus pipizcan, Wagler, Isis, 1831, p. 515 *, 
53* 
