On Moult and Col()ur-chan(/e in Birds. 177 



the known specimens have been met with in the Upper Shire 

 district, except those procured by Capt. Alexander on tlie 

 Zambesi (see Ibis, 1900, p. 431). 



14. Glaucidium peklatum (Shelley, Cat. p. 142). 



Shire R. ; c? ? , Banda. Native names: " Matuwese'' 

 and '' Kaungululu." 



15. Bubo lacteus (Shelley, Cat. p. 144). 

 Banda. Native name : " Linjichl." 



16. AsTURiNULA MONOGRAMMicA (Sliclley, Cat. p. 151). 

 Shire R. 



XIV. — On Moult and Alleged Colour-change in Birds. 

 By WiTMER Stone. 



The article by Mr. Bonhote, which appeared in last year's 

 volume of this Journal'^, leads me to make some reply 

 to his criticisms of my paper on " Moult " (published 

 in the ' Proceedings of the Philadelphia Academy,' 1896), 

 though it seems questionable whether any further discussion 

 will result in a better understanding of the phenomena of 

 plumag>^-change, since the advocates of both sides hold so 

 tenaciously to their own view's. 



Rather than repeat in detail arguments that have already 

 been fully expanded, I desire to point out some facts in 

 connexion with the study, and to endeavour to show what 

 has h&en proven by recent investigations. 



It will be understood at the outset that, with Dr. J. A. 

 Allen, Dr. J. Dwight, Jr., INIr. F. M. Chapman, and most 

 other American ornithologists, 1 maintain that all colour- 

 changes in bird-plumage are produced either by actual moult 

 or by abrasion of the tips, and that there is no change of 

 pigment in the feathers themselves. 



To consider in the first place the attitude of those wlio 

 differ from us, we note that the advocates of direct change 

 of pigment have been forced to abandon their earlier stand- 

 point — that most changes of plumage in spring-time were 



* See ' Ibis," 1!J00, p. 4G4. 

 SliR. VIII. — VOL. I. N 



