VII.-Rejections by Birds of Eggs unlike their own: with Remarks on some of the Cuckoo Problems

C. F. M. Swynnerton
1918 Ibis  
I27 deeper blue shade, and is even seen in this aberrant genus as a yellow-green patch. As the immature of the genus Purpureicephalus shows the evolution of the mature from a green bird, we have here a case of a structural differeuce developing at a more rapid rate than a colour-change. We are compelled to indicate our lack of knowledge of how colour-changes and structural changes are produced, but we do know that study of colour and colour-pattern will prove even more valuable than study of
more » ... le than study of structural differences. EXPLANATION OF PLATE III. The upper and under sides of the following Parrots :-1. Platycercus culadonicics. 2. " eleyane. 3. " Jtaveolus. 4. " adscitus. 5. " e.&ziua. 6 . Piirpicreicepiinlus spurius. 7 . I'l(itycerciis ictemti-s. 8. " tetiuxttcs. 9. Bamardius zonnrizu.
doi:10.1111/j.1474-919x.1918.tb00774.x fatcat:2lkha2tfubhyjeprwun5xqehqy