74 ON CROSSING AS A CAUSE Chap. XV 



wliich. h-ive been carefully recorded, concludes, " that from a 

 judicious pairing of cross-bred animals it is practicable to 

 establish a new breed." On the continent the history of 

 several crossed races of cattle and of other animals has been 

 well ascertained. To give one instance : the King of Wurtem- 

 burg, after twenty-five years' careful breeding, that is, after 

 six or seven generations, made a new breed of cattle from a 

 cross between a Dutch and a Swiss breed, combined with other 

 breeds.^^ The Sebright bantam, which breeds as true as any 

 other kind of fowl, was formed about sixty years ago by a 

 complicated croi^s.-*^ Dark Brahmas, which are believed by 

 Fome fanciers to constitute a distinct species, were un- 

 doubtedly formed'-^^ in the United States, within a recent 

 period, by a cross between Chittagongs and Cochins. With 

 plants there is little doubt that the Swede-turnip originated 

 from a cross ; and the history of a variet}"- of wheat, raised 

 from two very distinct varieties, and which after six years' 

 culture presented an even yample, has been recorded on good 

 authority. 2^ 



Until lately, cautious and experienced breeders, though 

 not averse to a single infusion of foreign blood, were al- 

 most universally convinced that the attempt to establish a 

 new race, intermediate between two widely distinpt races, 

 was hopeless : " they clung with superstitious tenacit}^ to the 

 " doctrine of purity of blood, believing it to be the ark in 

 " which alone true safety could be found." ^^ Nor was this 

 conviction unreasonable : when two distinct races are crossed, 

 the offspring of the first generation are generally nearly uni- 

 form in character ; but even this sometimes fails to be the 

 case, especially with crossed dogs and fowls, the young of 

 which from the fi.rst are sometimes much diversified. As 

 cross bred animals are generally of large size and vigorous, 

 they have been raised in great numbers for immediate con- 

 sumption. But for breeding they are found utterly useless ; 



" ' Bulletin de la Soc. d'Acclimat.,' " ' The Poultry Book,' by W. B. 



1862, torn. ix. p. 463. See also, for Tegetmeier, 1866, p. 58. 

 other cases, MM. Moll and Gayot, "* 'Gardener's Chronicle,' 1852, 



' Du Boeuf,' 1860, p. xxxii. p. 765. 



2^ ' Poultry Chvonicle,'' vol. ii., "^ Spooner, in ' Journal Royal Agri- 



1854, p. 36. cult. Sue.,' vol. xx., part ii. 



