201 
the Province of Buenos Ayres. 
every season except the spring. I shot one on the 17th Oc¬ 
tober last near Punta Lara, which was flying steadily in a 
north-westerly direction in company with another. Total 
length 13*5, beak L4, tarsus *5. Iris wood-brown; base and 
tip of beak dull yellow, remainder black; legs and feet dark 
red, between scarlet and carmine; head white, with a long 
black streak in front of and behind the eye; remainder of 
the plumage pearl-grey. On the 5th August I observed two 
Black-headed Terns fishing in some lagoons to the north of 
Buenos Ayres. They appeared to me to be Sterna cassini ; but 
I am not aware that that bird comes so far north as this*. 
-f- 137. Sterna superciliaris, Vieill.; Scl. et Salv. P. Z. S. 
1871, p. 571. 
Frequents shallow inland lagoons and small streams, and 
is also found in the river. Its habits resemble those of Sterna 
minuta at home. I observed specimens in May 1875 at 
Montevideo, and in April of the present year at Baradero. 
Iris wood-brown; beak and legs pale orange. 
138. Larus dominicanus, Licht. ; Scl. et Salv. 1. s. c. 
p. 576. 
Pretty common and generally distributed; but I have not 
seen it in the neighbourhood in the spring or summer. In 
the winter it wanders far inland. 
139. Larus cirrhocephalus, Vieill.; Scl. et Salv. 1. s. c. 
p. 578. 
I have not observed this bird to the south of Buenos Ayres, 
but have constantly seen it from March to July to the north 
of the city. Unlike Larus maculipennis, it never wanders 
inland, but frequents the shallow shores of the La Plata, 
feeding on dead fish or offal, and flocking round the fishermen 
when they are hauling their nets to get a share of the spoil. 
As a rule, this species does not mix with Larus maculipennis , 
though now and then they are seen together; but all the flocks 
or parties I have observed when flying from one spot to 
* [In our paper on Neotropical Laridse we have shown that this species 
is found as far north as Santa Catherina, Brazil (P. Z. S. 1871, p. 570) .— 
Epd.] 
