Interbreeding of Allied Species 



Moreover, species which differ only in colour 

 seem usually to interbreed in those parts where 

 they meet. 



"This interbreeding," writes Finn, on page 14 of 

 Ornithological and Other Oddities, " occurs where 

 the carrion crow (Corvus cor one) meets the hooded 

 crow (Corvus cornix), where the European and 

 Himalayan goldfinches (Carduelis carduelis and 

 C. caniceps) encounter each other, and where the 

 blue rollers of India and Burma (Coracias indicus 

 and C. affinis) come into contact, to say nothing 

 of other cases." 



Of these other cases, the Indian bulbuls of the 

 genus Molpastes form a very remarkable one. 

 In all places where two of the so-called species 

 meet they appear to interbreed, and so freely do 

 they interbreed that at the points where the allied 

 species run into one another it is not possible to 

 refer the bulbuls to either species. Thus William 

 Jesse writes of the Madras Red- vented Bulbul 

 (Molpastes hcemorrhous) (page 487 of The Ibis 

 for July 1902): "This bird, although I have 

 given it the above designation, is not the true 

 M. hcemorrhous. I have examined numbers of 

 skins and taken nests and eggs time after time, 

 and have come to the conclusion that our type is 

 very constant, and at the same time differs from 

 all the red-vented bulbuls hitherto described. 

 The dimensions tally with those given by Gates 

 for M. hczmorrhous, while the black of the crown 



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