Chap. VII. REVERSION AND ANALOGOUS VARIATION. 243 



rowly and symmetrically tipped or laced with white. I had 

 expected that some of the chickens whilst covered with down 

 would have assumed the longitudinal stripes so general with 

 gallinaceous birds ; but this did not occur in a single instance. 

 Two or three alone were reddish-brown about their heads. I 

 was unfortunate in losing nearly all the white chickens from 

 the first crosses ; so that black prevailed with the grandchildren ; 

 but they were much diversified in colour, some being sooty, 

 others mottled, and one blackish chicken had its feathers oddly 

 tipped and barred with brown. 



I will here add a few miscellaneous facts connected with 

 reversion, and with the law of analogous variation. This law 

 implies, as stated in a previous chapter, that the varieties of 

 one species frequently mock distinct but allied species ; and 

 this fact is explained, according to the views which I main- 

 tain, on the principle of allied species having descended from 

 one primitive form. The white Silk fowl with black skin 

 and bones degenerates, as has been observed by Mr. Hewitt and 

 Mr. K. Orton, in our climate ; that is, it reverts to the ordinary 

 colour of the common fowl in its skin and bones, due care 

 having been taken to prevent any cross. In Germany 30 a 

 distinct breed with black bones, and with black, not silky 

 plumage, has likewise been observed to degenerate. 



Mr. Tegetmeier informs me that, when distinct breeds are 

 crossed, fowls are frequently produced with their feathers 

 marked or pencilled by narrow transverse lines of a darker 

 colour. This may be in part explained by direct reversion to 

 the parent-form, the Bankiva hen; for this bird has all its 

 upper plumage finely mottled with dark and rufous brown, with 

 the mottling partially and obscurely arranged in transverse 

 Ames. But the tendency to pencilling is probably much 

 strengthened by the law of analogous variation, for the hens of 

 some other species of Gallus are more plainly pencilled, and 

 :m °f many gallinaceous birds belonging to other genera, 

 as the partridge, have pencilled feathers. Mr. Tegetmeier has 



TH <: ?SU HUhner und PkoenzucliV W. B. Tegetmeier, 1866, p. 222. I am 



uim, 1827, g. 17. For Mr. Hewitta indebted to Mr. Orton for a letter on 



statement with respect to the white the same subject. 

 fcuJc fowl, see the 'Poultry Book,' by 



R 2 



