The Making of Species 



yellow as in the normal type, and the plumage of 

 the back of the wings is longitudinally streaked 

 with white instead of barred. Several examples 

 of this form were found, along with normal young, 

 in the nest of one particular pair of little owls in 

 Italy, but the whole family were foolishly ex- 

 terminated by local ornithologists. 



The reed bunting (Emberiza schoeniclus) exists 

 in two distinct forms one having a much stouter 

 bill than the other (E. pyrrhuloides). This prob- 

 ably is an example of a mutation. 



The rare yellow-rumped Finch (Munia ftavi- 

 prymna), of Australia, has displayed a tendency 

 to change into the allied and far commoner 

 chestnut - breasted Finch ( M. castaneithorax] 

 during the lifetime of the individual (Avicultural 

 Magazine, 1907). Conversely, the male of the 

 common Red-billed Weaver (Quelea quelea) of 

 Africa has been found in its old age to assume 

 the characters of the comparatively rare Q. russi, 

 its black throat becoming pale buff as in that 

 form. 



Everyone is familiar with the chequered 

 variety of the common blue - rock pigeon, in 

 which the wings are regularly mottled with 

 black instead of being barred. This form some- 

 times occurs among wild birds, so that it has 

 been described as a distinct species. It is 

 important to note that there are red, dun, and 

 silver chequers as well as blue ones. 



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