LAEUS. 419 



N. Amer. Birds, 2nd ed. p. 21°; Saunders, Cat. Birds Brit. Mus. xxv. p. 185 ^ Gates, 

 Cat. Eggs Brit. Mus. i. p. 205 '. 



Ptil. cestiv. Supra margaritaceo-cinereus ; tectricibus alarum et secundariis intimis dorso conooloribus, his 

 exterioribus nigro terminatis ; ala spuria et tectricibus primariorum pure albis ; primariis albis, nigro 

 terminatis, interioribas cinereis, intimis cinereis, secundariis conooloribus ; uropygio et cauda pure albis ; 

 pileo, facie lateral! et gutture toto plumbescenti-nigris ; collo postico et laterali, et corpore subtus reliquo, 

 cum subalaribus et remigibus intus pure albis : rostro nigro ; pedibus leete aurantiaco-rubris, unguibus 

 nigris ; palpebris aurantiacis ; iride saturate brunnea. Long, tota circa 13-5, ate 10-4, caudae 3-9, 

 culm. I'B, tarsi 1"45. 



2 baud a mari distinguendus. Long, tota circa 12-5, alae 10-0. (Descr. maris et feminse ex Washington, D.C. 

 Mus. nostr.) 



Ptil. Tiiem. ptilosi aestivae similis, sed pileo nigro, postice et regione auriculari postica nigro notatis; pedibus 



carneis. 

 Juv. ptilosi hiemali similis, sed pileo fuscescenti-brunneo, plumis omnibus albido terminatis et subterminaliter 



brunnescentibus ; cauda nigro terminata distinguendus. (Descr. $ juv. ex Ipswich, Mass. Mus. 



nostr.) 



Hab. North America generally, breeding mostly north of the United States «. — Mexico, 

 Mazatlan {Grayson ^), Guanajuato, Guadalajara {Luges ^), 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 Duges ^ 

 and Sanchez *, 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 3. 



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-leayes 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 

 srqall and having a tendency to form an irregular and ill-defined zdne round the 

 lareer end ^. 



'to^ 



2. Lams franklini. 



Larus franklini, Swains. & Richards. Faun. Bor.-Amer., Birds, p. 424, t, 71 ' ; Scl. & Salv. P. Z. S. 

 1871, p. 577 "^ ; Baird, Brewer, & Ridgway, Water-Birds N. Amer. ii. p. 258 ' ; Ferrari-Perez, 

 Pr. U. S. Nat. Mus. ix. p. 179"; A. 0. U. Check-I. N. Amer. Birds, 2nd ed. p. 20°; 

 Saunders, Cat. Birds Brit. Mus. xxv. p. 191 '; Gates, Cat. Eggs Brit. Mus. i. p. 206'. 



Chroicocephalus franklinii, Lawr. Mem. Bost. Soc. N. H. ii. p. 317 '. 



Larus pipixcan, Wagler, Isis, 1831, p. 515". 



53* 



