472 Mr. C. H. B. Grant on Birds collected in Argentina, 



dashing contiuually past us witliiu a £c;w feet, ^vliile tlieir 

 combined cries Mere so deafening that we could hardly hear 

 eacli other speak. 



The nest is a mere hollow in the open sand, and three eggs 

 seem to be the complete clutch, but many bii-ds lay only two, 

 and quite a number of eggs were scattered about the bank, 

 rotten and often half covered with sand. 



There were also a few nestlings of all three species, and on 

 Oct. 2Gth, when we visited the same bank on the return south, 

 breeding was practically finished, and immbers of young were 

 just on the wing. 



At one bank visited on Sept. 21tii, fair numbers of both 

 the Terns and the Skimmers were breeding, but only one 

 pair of Sterna superciliaris, having two young just flown. 

 A great number of the nesting hollows were empty, and 

 we shortly discovered the reason why, for under a large 

 piece of dry wood mc saw and shot a large snake, which, 

 on being cut open, contained one adult and two young of 

 P. magnirostris. 



Fifty eggs were 1)rought home, taken at Colonia Risso, 

 Sept. 9th, near Puerto Braga, Sept. 24th, and Colonia Risso, 

 Oct. 26th. The majority of these agree with the description 

 given by Mr. Oates iu the Catalogue of Eggs, but some have 

 the ground stone-colour, and one set are of a yellowish olive. 

 They also vary greatly in the markings, some are evenly 

 marked all over as described in the Catalogue, others have 

 the greater number oE the markings at the larger end, often 

 forming a zone; some are finely spotted and blotched, and 

 these have the markings broad and often of a deeper brown 

 than that desciibed in the Catalogue, i. e. of a yellowish 

 ])rown and pale purple. They measure : axis 1'85 to 2*1 in., 

 diam. 1"4 to 1"). 



265. Sterna maxima. 



Sterna maxima Arg. Orn. ii. p. 195 ; Saunders, Cat. B. xxv. 

 p. 80. 



a. S ad. Tuyn, Aj6. ]\Iar. 1, 1910. 



This specimen is in full winter plumage. During the week 



