676 Letters, Extracts, Notices, ^c. 



said that when first caught it was coloured like any other 

 Song-Thrush, but had become darker at each moult during 

 the later years of its captivity. 



Now, in my experience (and I liave kept many examples 

 o£ both) an English Song-Thrush, even in captivity, is not 

 by any means such a long-lived bird as the common lilack- 

 bird : therefore for one to live to the astonishing age of 

 sixteen years is very exceptional*. 



Is melanochroisra in old age the result of unnsual con- 

 stitutional vigour, as leucochroism seems to be of constitu- 

 tional weakness? There is no doubt that white and pied 

 varieties of birds are the result either of in-breeding or of 

 failing strength : they undoubtedly become accentuated with 

 age, as I have noted in the case of all which I have possessed 

 (at various time>), and notably in the case of a Crimson- 

 eared Waxbill {Estrilda jj/ioenicotis) which I have had for 

 &ix or seven years, and which at the present time has the 

 greater part of its flight-feathers white. 



The abnormal variety of P. gouldm described above will 

 be presented to the Natural History Museum. It has been 

 fed upon white millet, spray-millet, and canary-seed ; there- 

 fore the change of colour is not due to unnatural feeding. 

 Yours &c., 



Arthur G. Butler, Ph.D., F.L.S., F.Z.S. 



124 Beckeuliam Ro ;d, 



Beckeuliam. 



28tli July, 1902. 



Sirs, — In the ' lb s' for July, when treating of the birds 

 collected by jNIr. R. M. Hawker on the White Nile, 

 Mr. Ogilvie-Grant remarked (pp. 462-463) on two male 

 Rufts in a peculiar state of plumage. The peculiarity 

 consisted in their heads and necks being more or less com- 

 pletely white. I think that it may be worth mentioning 

 that in the south of Spain, where in certain winters Ruft's 

 are fairly numerous, I have frequently noticed this phase of 

 plumage, exactly as described by Mr. Grant in birds from 



* I consider seven year.s in captivity a very good age for a IJlackbird : 

 tills is probably twice as long as it would live iu freedom. 



