842 BIRDS OF INDIA, 



The hind head is more or less crested, and the feet are more 

 fully webbed than in any other of the Terns. 



Bonaparte separates Pelecanopus from Thalasseus, placing under 

 the latter S. cantiaca of Europe ; affinis Riippell ; and bengalensis of 

 Lesson, with several American species ; whilst under Pelecanopus 

 he xa.uges pelecanoides, King; poliocej'cus, Gould, Torresii, Gould; 

 velox, Eiippell, and Bergii, Licht.* 



989. Thalasseus cristatus, Stephens. 



Sterna apud Stephens — Blyth, Cat. 1703 — S. pelecanoides, 

 King— Gould, Birds of Australia, VII. pi. 23 ?— S. velox, Rup- 

 PELL Faun. Abyss, pi. 13— S. "Bergii, Lichtenstein ?— 5. 

 poliocercus, Gould ? 



The Large Sea Tern. 



Descr. — Head, with the longish occipital crest, deep glossy- 

 black ; fore-head, lores, ear-coverts, nape, and all the lower parts 

 silky-white ; back, wings and tail rather darkish silvery-grey ; 

 edge of the wing and tips of the secondaries white ; quills dark at 

 the base and tip, hoary or silvery towards the terminal portion, with 

 the inner web and shafts white internally, diminishing in quantity 

 from the first. 



Bill pale yellow; irides dark brown ; legs black. Length 17 to 

 18 inches; wing 13 to 14 ; tail 7; bill at front 2^ ; tarsus 1;^. 

 The wini^s slie,htlv exceed the forked talk 



Without actual comparison of specimens, it is difficult to deter- 

 mine the identity of this Indian Sea Tern with the African and 

 Australian birds. Sjteoimens vary much in size and proportions 

 and in the length of bill. S. velox is said by Eiippell to be 15 

 inches long, to have the wing 14, and the bill 3|. S. pelecanoides 

 of Gould's Australia, appears from the drawing to be somewhat 

 larger than our bird ; and in S. poliocercus, the wing, as represented, 

 is nearly as long, being 13 inches. This last species is classed 

 by Gray under Sylochelidon, but surely this is a mistake. 



This fine Tern is found at the mouth of the Hooghly, does not 

 ascend the river to any distance, but follows ships out to sea 



rbtse SeaTemi esjjeciaiiy much raqiiirs a thorough revision and coiuparisou. 



