Chap. VII. REVERSION AND ANALOGOUS REVERSION. 251 



crossed with each other, or when crossed, with the exception 

 of G. banhiva, with the domestic fowl, produce infertile 

 hybrids. 



Finally, we have not such good evidence with fowls as 

 with pigeons, of all the breeds having descended from a 

 single primitive stock. In both cases the argument of 

 fertility must go for something; in both we have the im- 

 probability of man having succeeded in ancient times in 

 thoroughly domesticating several supposed species, — most of 

 these supposed species being extremely abnormal as compared 

 with their natural allies, — all being now either unknown or 

 extinct, though the parent-form of no other domesticated bird 

 has been lost. But in searching for the supposed parent- 

 stocks of the various breeds of the pigeon, we were enabled 

 to confine our search to species having peculiar habits of life ; 

 whilst with fowls there is nothing in their habits in any 

 marked manner distinct from those of other gallinaceous 

 birds. In the case of pigeons, I have shown that purely- 

 bred birds of every race and the crossed offspring of distinct 

 races frequently resemble, or revert to, the wild rock-pigeon 

 in general colour and in each characteristic mark. With 

 fowls we have facts of a similar nature, but less strongly 

 pronounced, which we will now discuss. 



Reversion and Analogous Variation. — Purely-bred Game, 

 Malaj r , Cochin, Dorking, Bantam, and, as I hear from Mr. 

 Tegetmeier, Silk fowls, may frequently or occasionally be 

 met with, which are almost identical in plumage with the 

 wild G. banhiva. This is a fact well deserving attention, 

 when we reflect that these breeds rank amongst the most 

 distinct. Fowls thus coloured are called by amateurs black- 

 breasted reds. Hamburghs properly have a very different 

 plumage ; nevertheless, as Mr. Tegetmeier informs me, " the 

 great difficulty in breeding cocks of the golden-spangled 

 variety is their tendency to have black breasts and red backs.' 

 The males of white Bantams and white Cochins, as they 

 come to maturity, often assume a yellowish or saffron tinge ; 

 and the longer neck hackles of black Bantam cocks," 28 when 



29 Mr. Hewitt, in 'The Poultry Book,' by W. B. Tegetmeier, 1866, p. 248. 



