372 



MK. E. DEGEN OX ECDTSIS. 



It was a great satisfaction to me therefore when, on December 11th, I received the 

 first specimen of a young female, numbered 14, wliich sh(jwed evidence of tlie moult 

 for three out of the four feathers on Iwth wings. A second bird, forming part of the 

 same weekly complement, and whicli had received the serial number lo on account of 

 having been examined before the former, also a young female, exhibited no traces 

 of moult for this part. This difference may be accounted for by the latter specimen 

 being more backward in moult than No. 14 as regards one or two of the metacarpo- 

 digital and one of the cubital remiges. 



The next weekly instalment, consisting of four specimens, contributed nothing 

 further to this stage of the moult. Curiously enough, another young female. No. 19 

 of the series, supplied the desired evidence for the whole of this set of feathers in such 

 an excellent manner for both wings alike that nothing could be more perfect for a 

 demonstration of the graduated succession of their growth, as seen in text-fis. .3, 

 from my drawing of its right wing. 



Text-fie. 3. 



Carpal covert. 



Metacarpal. 



Alula of right wins. 



Showing the successive stages of development of the quills composing the Alula, 



from without inwards. 



The figure shows the fourth longest and outermost feather, if not perfectly freed 

 at its base from the capsula, to have at least acquired its ultimate full length. 

 The next inner one, whose adhering capsule remains and encloses a greater amount 

 of the new growth in proportion to the former, shows it to be about f of its eventual 

 length. The third innermost, being remex II., and the next in rotation of development, 

 has attained one-half of its length ; whilst remex I., or the innermost and last to appear, 



