Chap. VII. RE VERSION AND ANALOGOUS REVERSION. 255 



white, acquired as they grew old a few black feathers. A 

 hen from the white G ame, which was for a long time entirely 

 black glossed with green, when two years old had some of 

 the primary wing feathers greyish- white, and a multitude of 

 feathers over her body narrowly and symmetrically tipped or 

 laced with white. I had expected that some of the chickens 

 whilst covered with down would have assumed the longi- 

 tudinal 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 

 maintain, 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, 



30 « Die Hiihner- und Pfaueuzucht,' W. B. Tegetmeier, 1866, p. 222. I am 



Ulm, 1827, s. 17. For Mr. Hewitt's indebted to Mr. Orton for a letter on 



statement with respect to the white the same subject. 

 Silk fowl, see the ' Poultry Book,' by 



