422 LAEID^. 



The nest is simply a depression in the soil, with a slight lining of dry grass. 

 The eggs are olive-buff, with spots and small blotches of various shades of brown, 

 sometimes collected near the larger end, with inconspicuous spots of pale underlying 

 purple ^5. 



4. Lams heermanni. 



Larus heermanni, Cass. Pr. Acad. Phil. 1852, p. 187 'j Salv. Ibis, 1865, p. 190'; 1866, p. 198' ; 



Scl. & Salv. P. Z. S. 1871, p. 574*; Baird, Brewer, & Ridgway, Water-Birds N. Amer. ii. 



p. 252 ' ; A. 0. U. Check-1. N. Amer. Birds, 2nd ed. p. 20 ° ; Saunders, Cat. Birds Brit. Mus. 



XXV. p. 225 ' ; Nelson, N. Amer. Fauna, no. 14, p. 23 '. 

 Blasipus heermanni, Coues, Ibis, 1864, p. 388 ° ; Lawr. Mem. Bost. Soc. N. H. ii. p. 317 ". 



Supra schistaceus, alis saturatioribus, remigibns nigricantibus, primariis inlimis anguste et secundariis 

 latius grisescenti-albo terminatis ; tectricibus primariorum extns grisescenti-albidis ; sopracaudalibns 

 cineraceis ; cauda nigra, albo termiuata ; collo undique et corpore subtus pallide cineraceis, abdomioe 

 dilutiore; pileo, faciei lateribus et guttnre toto albis; subalaribas et remigibus intas plumbescenti- 

 bruuneis, axillaribus cinerascentioribus : rostro rubro, nigro ssepius terminato ; pedibus nigris ; iride 

 brannescenti-grisea ; annulo periophtbalmico rubro. Long, tota circa 18-0, alaa U-O, caudae 5'4, 

 culm. 2-0, tarsi 2-0. (Descr. maris adulti ex Monterey. Mus. Brit.) 



5 mari similis, sed paullo minor et rostro debiliore. 



Ptil. Mem. ptilosi sestivse similis, sed pileo et facie lateral! cum guttnre imo grisescenti-fusco striolatis, gula 

 tantura albida : rostro pallide rubro, nigro latius terminato. (Descr. feminae adullse ex Santa Barbara. 

 Mus. nostr.) 



Jmi. Fuliginoso-brunneus, notaei plumis plurimis paUidiore brunneo marginatis: subtus vix cinerascente 

 lavatis. (Descr. avis jun. ex Chiapam. Mus. nostr.) 



Hab. Pacific Coast of North Ameeica from British Columbia southward ^ ^. — Mexico, 

 coast of Western Mexico (Aberf^), Mazatlan (Grayson^"), Isabel I., off San Bias 

 {Grayson^^, Nelson^), Tres Marias Is., Maria Cleofa I. {Nelson^); Guatemala, 

 Pacific coast ^ *, Chiapam 2^9, San Jose ^ (0. S.). 



This is a member of a small group which is restricted to the Pacific, and is, more- 

 over, confined to the American side, with the exception of L. crassirostris of Japan and 

 China. Heermann's Gull occurs on the Pacific side of North America durins the 

 breeding-season, and migrates south along the Pacific coast of Central America as far as 

 Chiapam in Guatemala, where Salvin met with some young birds on the shore and 

 lagoons in January ^. Grayson shot specimens of L. heermanni near Mazatlan in 

 February and March, and considered it to be only a winter visitant ^^ ; but he appears 

 to have afterwards found it breeding, as an egg in the U. S. National Museum procured 

 by him is recorded as being from that locality ^. 



Mr. E. W. Nelson met with two or three pairs on Isabel Island, and half a dozen 

 others about the Tres Marias. He found a nest on May oOth, which had been occupied 

 earlier in the season, on a rocky islet off the shore of Maria Cleofa, and full-grown 

 young were also seen on the rocks. The old birds pursued the Blue-footed Gannets 

 in pairs, and forced the latter to disgorge the fish they had captured. He remarks 

 that the Gulls are bold and noisy aggressors when they wish to take advantage of 



