Paraguay , Bolivia , and Southern Brazil. 
475 
resident, breeding, I was told, near Cape San Antonio. In 
its habits it resembles L. marinus. 
270. Larus maculipennis. 
Larus maculipennis Arg. Orn. ii. p. 198 ; Saunders, Cat. 
B. p. 200. 
a. ? ad. Los Ynglases, Ajo. 
b. S imm. „ „ 
c. J itnra. „ 
d. $ ad. „ 
e. S ad. ,, 
/. $ ad. Luiconia, 
Sept. 11, 1908. 
Sept. 11, 1908. 
Oct. 14, 1908. 
Jan. 14, 1909. 
Jan. 27, 1909. 
Feb. 2,1909. 
Los Ynglases, Ajo. 
Feb. 9, 1909. 
Apr. 3, 1909. 
Apr. 14-20, 1909. 
June 11, 1909. 
Dec. 22-23, 1909. 
Jan. 18, 1910. 
g. S young. 
h. $ imm. 
i. j. S ? ad. 
k. S ad. 
/, m. S ad. 
n. S ad. 
This is the commonest Gull in the Ajo district, and is 
resident; but, owing to the dry seasons, it did not breed 
in the camp, and I believe repaired to Cape San Antonio 
for that purpose. It was also observed some way up the 
Parana, and I have recorded that several were seen near 
La Paz, N. Argentine, with completely brown heads, on 
July 17. 
271. Larus cirrhocephalus. 
Larus cirrhocephalus Arg. Orn. ii. p. 201 ; Saunders, Cat. 
B. xxv. p. 198. 
a. $ ad. Los Ynglases, Ajo. 
b. $ imm. ,, „ 
c. ? ad. „ „ 
d. d ad. „ ,, 
ej. ? ad. „ ,, 
g. $ imm. „ „ 
h. d ad. ,, ,, 
The Grey-headed Gull makes 
district after the breeding-season 
Mar. 29, 1909. 
Mar. 29, 1909. 
Mar. 30, 1909. 
Mar. 31, 1909. 
Mar. 31, 1909. 
Apr. 1, 1909. 
Apr. 10, 1909. 
its appearance in the Ajo 
and remains throughout the 
