LARUS. 



217 



Three eggs of Audouin's Gull in the Collection have a buff 

 ground and are pretty thickly spotted and blotched with blackish 

 brown. A fourth is of a kind of creamy-buff tint, and the mark- 

 ings, which are similar in character to those on the other examples, 

 are of a pale yellowish-brown colour. All four have the usual 

 pale purple underlying markings. They measure respectively : 

 2-4 by 1-75; 2-45 by 1'73; 2'45 by 1-8 ; 2-53 by 1-66. 



]. Columbretes Island, Spain. Saunders Coll. 



1. Columbretes Island, 1st May. Saunders Coll. 



1 . ( 1 olumbretes Island, April. Saunders Coll. 



1. Toro, Sardinia, 25th May (Lord Saunders Coll. 

 LUford). 



Lams delawarensis, Ord. 

 (Plate XVII. fig. 5.) 



Lams delawarensis, Baird, Brewer fy Ridgw. Water Birds N. Am. ii. 

 ]>. 244 (1884); Saunders, Cat. Birds B. M. xxv. p. 273 (1896); 

 Sharpe, Hand-l. i. p. 142 (1899). 



The two eggs of the Ring-billed Gull in the Collection are of 

 quite dissimilar types. One is of a regular oval form and has an 

 olive-buff ground, sparingly marked, except at the larger end, where 

 there are huge confluent blotches forming an irregular zone, with 

 spots and specks of deep chocolate-brown ; the underlying pale 

 purple markings are few and inconspicuous. The second specimen 

 is a pointed oval and has a light buff ground, boldly marked all over 

 with spots and blotches of blackish brown. The underlying mark- 

 ings on this egg are numerous, large and conspicuous. The two 

 measure respectively : 2-25 by 1*63 ; 2*35 by 1'6. 



1. Little Slave Lake, Canada (S. Jones : Salvin-Godman Coll. 



Ilenshaw Coll.}. 

 1. North America. Saunders Coll. 



Larus californicus, Lawr. 

 (Plate XVIII. fig. 2.) 



Larus californicus, Baird, Brewer fy Ridgw. Wafer Birds N. Am. ii. 

 p. 242 (1884); MacFarlane, Proc. U.S. Nat. Mus. xiv. p. 418 

 (1891); Saunders, Cat. Birds B. M. xxv. p. 276 (1896) ; Sharpe, 

 Hand-l. i. p. 142 (1899). 



The eggs of the California Gull in the Collection show con- 

 siderable variation, but can all be matched by those of L. fnscus, 

 and a larger series would, no doubt, display all the types to be found 

 among the eggs of that species. They measure from 2*45 to 2*75 

 in length, and from 175 to T85 in breadth. 



1. North America (Smiths. Inst). 

 1. North America (T. M. Brewer). 

 1. North America, 16th May 



(R. Ridgway). 

 1. Anderson Kiver, Arctic America, 



6th July (R. MacFarlane). 



Salvin-Godman Coll. 

 Saunders Coll. 

 Saunders Coll. 



Saunders Coll. 



