520 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 49. 



THALASSEUS BERGII EDWARDSI Mathews. 



Thalasseus bergii edwardsi Mathews, Birds of Australia, vol. 2, pt. 3, September 

 20, 1912, p. 347 (Ceylon). 



Suhspecific characters. — Resembling Thalasseus hergii hakeri, but 

 decidedly smaller. 



Measurements. — Wiiig, 347-351 (average, 349) mm.; tail, 162-181 

 (171.5); exposed culmen, 61.5-65 (63.3); tarsus, 31.5-32.5 (32).^ 

 Wiiig, 345-384 (average, 359.6) mm.^ 



Geographical distribution. — The coasts of southern India and of 

 the Bay of Bengal; west to the Laccadive Islands; south to Ceylon 

 and Tenasserim; east to Tenasserim and Burma; and north to the 

 mouth of the Ganges River and the Laccadive Islands. 



This race is, in size at least, much nearer Thalasseus hergii velox 

 than to Thalasseus hergii hakeri, which is geographically adjacent; 

 but it is even smaller than the former, as well as apparently some- 

 what darker above. The two specimens examined measure as 

 follows: 



Measurements of specimens of Thalasseus hergii edwardsi. 



THALASSEUS BERGII CRISTATUS (Stephens). 



Sterna cristata Stephens, Shaw's Gen. Zool., vol. 13, pt. 1, 1826, p. 146 ("China 

 and many of the southeastern islands of Asia. " Definitely fixed as China by 

 Mathews, Birds of Australia, vol. 2, pt. 3, September 20, 1912, p. 347). 



Sterna bergii boreotis Bangs, Bull. Mas. Comp. Zool., vol. 36, 1901, p. 256 (Ishigaki 

 Island, Riu Kiu Islands, Japan). 



Suhspecific characters. — Like Thalasseus hergii edwardsi, but much 

 smaller. 



Measurements. — Wing, 308-344 (average, 325.7) mm.; tail, 135- 

 178 (160.3); exposed cuhnen, 55-62 (57.3); tarsus, 27-28 (27.6).* 

 Wing, 324-344 (average, 333.5) mm.^ 



Geographical distrihution. — Coast and islands of southeastern Asia 

 north to Fu Chau, China, and the Riu Kiu Islands, Japan; south- 



' Two specimens, from Tenasserim. 



8 Seven specimens, measured by Stresemanu. 



* Used in measurement averages on p. 520. 



* Four specimens, from China, Japan, and the Philippine Islands. 

 6 Eleven specimens, measured by Stresemanu. 



