THE NATURAL HISTORY SURVEY. 3! 



Lams delawarensis Ord. Ring-billed Gull. 



Larus delawarensis OBD, Guthrie's Geog., 2d Amer. ed., 1815, 319. 



A common winter resident, staying in our vicinity from about 

 the last of September until about April 29. This species is often 

 confounded with the Herring Gull unless the two are seen to- 

 gether, when it will be noticed that the Ring-billed Gull is much 

 the smaller of the two, and that the light greenish bill is crossed 

 by a dark band near the tip. 



This is a characteristic gull of North America ; and in winter 

 it may be seen as far south as Cuba and Mexico. 



Lams Philadelphia (Ord). Bonaparte's Gull. 



Sterna Philadelphia OBD, Guthrie's Geog., 2d Amer. ed., II, 1815, 319. 

 Larus Bonapartii NUTTALL, Manual, II, 1834. 294. 

 Larus Philadelphia GBAY, List Brit. B., 18G3, 235. 

 Popular synonyms: MOLLY GULL. SEA PIGEON. 



A transient visitor in Cook County, arriving in April, when 

 it stays but a short time. It returns again in September and 

 remains with us until the middle of November. This beautiful 

 and friendly little gull may be found on all of our large lakes, 

 and at times the lagoons in Jackson and Lincoln parks will 

 seem to be covered with them. The water at this time will be 

 alive with immense schools of minnows, and the gulls while feed- 

 ing dive after them, tern-like. 



The range of Bonaparte's Gull extends over the whole of 

 North America, though it seldom breeds south of the British 

 Possessions. 



Genus XEMA Leach, 1819. 



Xema sabinii (Sabine). Sabine's Gull. 



Larus sabinii J. SAB., Trans. Linn. Soc., XII, 1818, 520, pi. 29. 

 Xema sabini LEACH, App. Ross's Voy. Baffin's Bay 4to. ed., 1819, Ivii. 

 Xema sabinii LAWB. in BAIBD, B. N. Amer., 1858, 857. 

 Xema sabinei COUES, Proc. Acad. Nat. Sci. Philadelphia, 1862, 311. 

 Popular synonym: FOBK-TAILED GULL. 



The only record that I can find regarding the taking of this 

 bird within the limits of our area is that of Mr. E. W. Nelson, 

 who says : "While collecting on the Lake shore near Chicago, the 

 first of April, 1873, I saw a specimen of this bird in a small pool 

 of water on the beach. At first I supposed it was a Bonaparte's 

 Gull, and was about passing it, when it arose, and as it passed 

 toward the lake I saw it was something new to me, and fired. It 



