332 ON THE GENUS PITTA. 



do not appear to be constant, but vary in all the birds of this section 

 according to age, are not sufficient to establish a species. Nor do I think 

 that the extent of white on the primaries is of specific value, as I find that 

 specimens from the same islands vary in this mark very considerably ; and 

 I am inclined to believe that the one separated as P. muelleri on account of 

 the primaries being all white, is only an adult of P. atricapilla. Specimens 

 of so-called P sanghirana which I have examined do not agree together in 

 the extent of white on the primaries ; and if this mark were of specific value, 

 they should be separated. But my examination of the specimens lately 

 placed at my disposal, together with (through Mr. G. R. Gray's kindness) 

 those contained in the British- Museum collection, leads me to the conclusion 

 that those birds of this section with white on their primaries have but a 

 comparatively small extent of it when young, and that it increases in 

 successive moults as the bird grows older, until it occupies almost the whole 

 feather, the end only being tipped wdth black, as we see in so-called 

 P. muelleri, which, according to my view, is only the adult form of 

 P. atricapilla.^^ 



Lord Tweeddale (then Lord Walden) says (Trans. Zool. Soc. vol. ix. 

 part 2, p. 188) :— 



" Six species of black-headed green-bodied Pittce are fully established as 

 meriting specific distinction : — 



"1. P. novce-guinece, Miiller & Schlegel. New Guinea and the Aru 

 Islands, and most of the Papuan Islands. 



2. P. sanghirana, Schlegel. Sanghir Islands. 



3. P. rosenhergii, Schlegel. Soek Island, in the Bay of Geelvink. 



4. P.forsteni, Bp. Celebes. 

 6. P, muelleri, Bp, Borneo. 



6. P. sordida (L. S. Miiller) Philippines. 



