(2078) Thalasseus bergii cristata.
THE CHINESE LARGE CRESTED TERN.
Sterna cristata Stephens, Gen. Zool. (Shaw), xiit,pt. 1, p. 146 (1826) (China). Sterna bergii. Blanf. & Oates, iv, p. 314 (part,).
Vernacular names. None recorded.
Description. A small race very similar to T. b. edwardsi but paler above.
Colours of soft parts as in the other races.
Measurements. Wing 322 to 357 mm.; culmen 59 to 67 mm.
Distribution. Coasts of China, Indo-Chinese countries and the islands of the Mergui Peninsula.
It is with some hesitation I admit this race to our Avifauna but two specimens from Southern Tenasserim, possibly casual visitors only, seem nearer to it than to edwardsi, which is the breeding bird in that locality.
Nidification. In 1896 I received from an island in the Mergui Peninsula skins and eggs of a Crested Tern which were possibly of this race, whilst "Williamson and Herbert took eggs on small islands in the Gulf of Siam. They found single eggs laid on the bare rock with no nest. Thirty-two eggs average only 58.7 X 41.8 mm.; much smaller than the eggs of other races.
Habits. Those of the species.
* Non-breeding birds occasionally wander great distances and make measurements sometimes unreliable. Thus a dark bird with a wing of 385 mm. waft obtained off the Malay coast.. Another difficulty is the large number of unsexed birds in the British Museum collection. Measurements of sexed breeding birds make the differences of the various races much more distinct.