476 Mr. C. H. B. Grant on Birds collected in Argentina, 
winter, consorting with L. maculipennis in flocks of thousands 
and feeding largely on the carcases of dead stock. It can 
be picked out from L. maculipennis by its larger size and 
darker colouring, and the call is also louder and harsher. 
272. Stercorarius crepidatus. 
Stercorarius crepidatus Saunders, Cat. B. xxv. p. 327. 
a. d imm. Tuyu, Ajo. Feb. 21, 1909. 
This specimen is moulting all over, except the wings. 
Its occurrence apparently constitutes a new record for 
Argentina, this species not having, I think, been recorded 
before south of Bio de Janeiro. It was met with chasing 
some Gulls on the sea-coast. On Feb. 23, 1910, I saw a 
very dark-plumaged Skua chasing a Gull on the coast close 
to where the specimen was shot in the previous year, and on 
the following day a browner specimen was observed ; I have 
no doubt that both these birds were of this species, but 
unfortunately I was unable to get a shot at them. 
Fam. PoniciPEDim®. 
273. iEcHMOPPIORUS MAJOR. 
JEchmophorus major Arg. Orn. ii. p. 202; Ogilvie-Grant, 
Cat. B. xxvi. p. 549. 
a, b. £ $ . Los Ynglases, Ajo. Oct. 13, 1908. 
Both these specimens are in full breeding-dress. This 
Grebe is not uncommon in the Ajo district, but is a rather 
wary bird and therefore difficult to shoot. In habits and 
appearance it resembles the larger European species. It 
breeds in the district, though I did not succeed in finding a 
nest. 
274. PoDICIPES AMERICANUS. 
Podiceps americanus Grant, Cat. B. xxvi. p. 524. 
Podiceps rollandi Arg. Orn. ii. p. 204. 
a. ^ ad. Los Ynglases, Ajo. Oct. 13, 1908. 
b. ad. „ „ May 9, 1909. 
This is quite the commonest Grebe in the Ajo district. 
It is usually seen singly or in pairs on all the waters; 
