Strong — Developivient of Color tn Feathers. 



Jt'l/.te; 6. 



^^'• 



k' 



• ^ 



? 



X 



ynm.p(fj. 



rvl'pl. 



iiL 



\V 



tnrm.])ifj. 



r^ 





30 





*!,•*«. 



y 





rial. 



35 



36 



MS. del. 



