STERNA CANTIACA 355 



Pacific coast appears to be that recorded by Salvin from Guatemala, 

 but as the isthmus is very narrow at this point, it is probable the 

 specimen obtained had strayed across from the other side. 



The present species is less exclusively a coast frequenting species 

 than are most of the Terns, and is far more often to be found in 

 inland localities than others of the genus. It is fond of salt-water, 

 however, and has a partiality for lagoons and deltas sheltered from 

 the open sea, though also to be met with frequently on fresh-water 

 lakes and large rivers. The Tunisian Sebkas are often visited by the 

 bird on passage, and the species probably breeds on the larger of 

 them, as it does at Zana. 



S. anglica is generally to be found in small flocks, though 

 occasionally in large numbers. 



Its flight is very graceful, and fairly swift and powerful. Its notes, 

 which have been rendered by the syllables " ef-ef" and " af-af," axe 

 rather Gull-like. 



In its diet this species differs from most other Terns in being par- 

 ticularly fond of insects, Orthoptera, Lepidoptera and Coleoptera 

 being all greedily eaten by it. In countries like Tunisia and Algeria, 

 where locusts are a plague, these provide the bird with an abundance 

 of food. It also feeds on fish, crustaceans, frogs, &c., and may almost 

 be called omnivorous. 



The species breeds in colonies, and deposits its eggs, two or three 

 in number, in a depression in the bare ground. The colour of the 

 eggs varies from a very pale buff to a darker or sometimes a greenish- 

 buff, the underlying spots being pale grey, and the surface-spots 

 brown. Average measurements 50 X 35 mm. 



STERNA CANTIACA, Gmelin. 

 SANDWICH TEEN. 



Sterna cantiaca, Gmel. Syst. Nat. i, p. 606 (1766) ; Malherbe, Cat. Eais. 



d'Ois. Alcj. p. 22 (1846) ; Koenig, J. f. 0. 1888, p. 286 ; id. J. f. 0. 



1893, p. 97 ; Saunders, Cat. Birds Brit. Mus. xxv, p. 75 ; Erlanger, 



J. f. 0. 1900, p. 72. 

 Thalasseus cantiacus, Loche, Expl. Sci. Alg. Ois. ii, p. 199 (1867). 



Description. — Adult male, spring, from Djerba, South Tunisia. 

 Forehead, crown and nape jet-black ; neck, mantle, rump, tail and wing- 



