117. THALASSOGERON CULMINATUS (Gould). 



(GREY-HEADED ALBATROS.) 

 (Plate 10L) 



Diomedea chlororhynchos (nee Gm.), Audub., Orn. Biogr. V., p. 326 (1839) ; Lawr. 

 in Baird, Cassin and Lawrence, Birds N. Amer., p. 822 (1860). 



Diomedea culminata, Gould, P.Z.S., 1843, p. 107 ; Ann. and Mag. Nat. Hist., XIII., 

 p. 361 (1844) : id., Birds Austr., VH., PI. 41 (1848); id., Handb. Birds 

 Austr., IV., p. 436 (1865); Sharpe, Phil. Trans., Vol. 168, p. 147 (1879). 



Thalassarche culminata, Giglioli, Faun. Vertebr. Oceano, p. 59 (1870). 



Thalassogeron culminatus, Ridgway in Baird, Brewer, and Ridgway, Water-Birds 

 N. Amer., II., p. 358 (1884) ; Salvin, Cat. Birds Brit. Mus., XXV, p. 451 

 (1896); Sharpe, Rep. Coll. "Southern Cross," p. 162 (1902); Wilson, Nat. 

 Antarctic Exped., II., Aves, pp. 113, 114. 



Minor : culmine flavo, usque ad frontem basalem producto ; mandibula quoque 

 basaliter flava ; interscapulio cineraceo, pileo toto clare cinereo ; facie guttureque 

 concoloribus. 



The Grey-headed Albatros was placed by Salvin in the genus Thalassogeron chiefly 

 on account of its having an intervening space of bare skin between the base of the 

 latericorn and that of the culminicorn, but after examining a long series I find that 

 this membrane varies so much in extent that an almost perfect gradation in this 

 respect is found between Diomedea and Thalassogeron. Nevertheless the osteological 

 differences mentioned by Mr. Pycraft in the Introduction to this Monograph (p. xix) 

 indicate that there is ample reason for the separation of the two genera. 



T. culminatus has been compared to Diomedea bulleri, a characteristic Diomedea 

 without any intervening patch of bare skin at the base of the mandible, but besides 

 this difference, the colour of the mantle in T. culminatus is of a much clearer grey, 

 and the entire crown, sides of the face and throat are of a delicate blue-grey, and no 

 white frontal area is visible. 



Although resembling T. chlororhynchus in its general features T. culminatus 

 has a much stouter and deeper bill, a feature which was observed by Gould, and 

 figured, though not quite correctly, by Mr. W. L. Sclater, in the " Fauna of South Africa" 

 (Vol. IV., p. 504, fig. 155). It differs, too, in the manner in which the culminicorn reaches 

 the base of the mandible, impinging on the feathers of the forehead, whereas in 



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