BIRDS FROM SIAM AND THE MALAY PENINSULA 101 



Tliis form differs from S. a. sinensis and S. a. pusilla in having the 

 shafts of the three outer feathers dark. 



Robinson and Kloss ^^ report this tern as occurring in some numbers 

 in the winter in the Straits of Malacca, but apparently the above are 

 the only definite Siamese records. 



The form ranges from the Red Sea and Somali coasts east to the 

 Malay Peninsula. 



STERNA ALBIFRONS SINENSIS Gmelin 



Sterna sinensis Gmelin, Sy sterna naturae, vol. 1, pt. 2, p. 608, 1789 (China). 



One male, two females, and one unsexed, Lem Sing, Chantabun, 

 June 8, 14, 1926. 



This small series agrees very well with a small series from China 

 in size and color. The culmens in five breeding males from China 

 measure 30, 30, 30.5, 31.5, and 32 mm. The single male from Lem 

 Sing measures 32.5 mm. The four breeding females from China 

 have culmen measurements of 27, 29, 29, 29.5 mm. Two females 

 from Siam have culmen measurements of 28.5 and 29 mm. 



The form ranges from the coast of Ceylon and Burma to Siam, 

 China, Korea, Indo-China, and the Malay Peninsula. It is migratory 

 in the northern part of its range but probably resident in the south. 



Baker ^^ records two females taken at Meldong, June 27; William- 

 son *^ took it at Koh Lak and Hua Hin in June; de Schauensee *^ took 

 a female at Bangkok on March 9 and reports it common there over 

 the Menam. 



THALASSEUS BERGD EDWARDS! Mathews 



Thalasseus bergii edwardsi Mathews, The birds of Australia, vol. 2, pt. 3, p. 347, 

 1912 (Ceylon). 



Two males, Nakon Sritamarat, September 20, 1926. 



Specimens of this form have been recorded from Tanjong Patani. 

 Williamson ^° found it breeding on some small islands in the Gulf of 

 Siam (Koh Rin and Koh Phai) in May 1918. Robinson ^' has recorded 

 specimens from Pulo Terutau and Pulo Langkawi, taken in February 

 and March; Herbert ^- reports it breeding on Koh Samui, Bandon. 



The two males from Nakon Sritamarat agree with a male and female 

 collected by Dr. W. L. Abbott at Bok Pyin, Tenasserim, February 9, 

 1900. The wings of the Nakon males measure 350 and 362 mm, the 

 culmens 59 and 65 mm. Oberholser ^^ places the Bok Pyin specimens 

 under Thalasseus bergii edwardsi. In the absence of additional speci- 

 mens I am regarding all Siamese records as of this race. 



»» Journ. Nat. Rist. Soc. Siam, vol. 5, p. 53, 1921. 



»' Journ. Nat. Hist. Soc. Siam, vol. 4, p. 40, 1920. 



" Journ. Nat. Hist. Soc. Siam, vol. 3, p 37, 1918. 



»» Proc. Acad. Nat. Sci. Philadelphia, vol. 80, p. 579, 1928. 



•» Journ. Nat. Hist. Soc. Siam, vol. 3, p. 83, 1919. 



«• Journ. Federated Malay States Mus., vol. 7, p. 143, 1917. 



«' Journ. Siam Soc. Nat. Hist. Suppl., vol. 6, p. 348, 1926. 



•» Proc. U. S. Nat. Mus., vol. 49, p. 520, 1915. 



