50 MESSRS. ROBINSON AND KLOSS ON 



Thalasseus herijii ])elecanoides, J., p 143 (Teintau). 



The Malayan material in our possession, though larger than 

 that in the hands of Mr. Oberholser, is not sufficient to enable us 

 satisfactorily to discriminate the local races of these sea-terns, our 

 area being apparently the meeting places of three nominal forms, 

 viz , 8. h. ci'istatus, S. h. edxvardsi and 8. h. 'pelecanoidex, but the 

 balance of probability is that the birds on the eastern side of the 

 Peninsula will prove to be S. h. crlstatu-^, while, according to 

 Oberholser, those from the west should, be S. h. edivardsl. We are 

 unable to separate Terutau and Langkawi birds from Tioman and 

 Rhio Island specimens which, fide Oberholser, should be *S'. h. 

 pelecanoides King. 



We have examined nine fully adult birds in fresh breeding 

 plumage from various islands in the Inner Gulf of Siam. Eight 

 males have the wing 334-3G0 mm. and a female 335, the median 

 beinw 347 nun. On the whole, therefore, we refer all Malayo- 

 Siamese birds to the Australian aS'. h. 'pelecanoides. 

 Sterna media Horsf. 



S lev nu media, HorsQeld, Trans. Linn. Soc. xiii, 1821, p. 198 (Java) ; 

 Howard Saunders, Cat. Birds Brit. Mus. xxv, 1896, p. 86. 



This large tern, which is easily recognised by its somewhat 



slenlor, yellow-orange* bill, is .sparingly distributed in the Straits of 



Malacca. We have obtained it north of Penang, and there is little 



doubt that it will be found on the coast of west Siam : though it is 



only doubtfully recorded from the Tenasserim coast. It will not, in 



all probability, be found on the eastern side. 



52. Sterna fluviatilis tibetana Saunders. 



Sterna tibetana, Saunders, P. Z. S. 1876, p. 649 (Thibet) ; Hume, 



Stray Feath. viii, 1879, p. L'38 (Tongka). 

 Sterna longij^emiis, Siumders, Cat. Birds Brit. Mus. xxv, 1896, 



p. 60, spins, u., v. 

 Stern' I fluviatilis tibetana, J., p. 142 (Terutau). 



Terns of this group are conation in the Straits of Malacca, 



and have been referred indifferently to the common European tern 



A. Huiiu! .V Diivisim, Stray Kcatlicrs, vi, 1878. E. (). (Irant, Fiisciculi Malayenses, iii (Birds), 190.5, 



B. Miillcr, ])ii' Oiiiis ik-r liiscl Salaiiwi, IHH'i. F. Holnnson and Kloss, Ibis, 1910-11. 



C. ()at<w, liji-ds lirit. Biirniali, Vols, i \- ii, 1883. G. (iairdncr, Joiirn. N. H. Soc. Siam, i, 1915. 



D. Bonhote, B. Z. S. 1901, Vol. i. H. Uobiiison, .Joiiin. >'. 31, S. Museums, v, 1915. 



JOUKN. NAT. HIST. SUC. SIAM. 



