Chap. XV. OF THE MODIFICATION OF EACES. 97 



diversified. As cross-bred animals are generally of large size 

 and vigorous, they have been raised in great numbers for 

 immediate consumption. But for breeding they are found to be 

 utterly useless; for though they may be themselves uniform in 

 character, when paired together they yield during many gene- 

 rations offspring astonishingly diversified. The breeder is driven 

 to despair, and concludes that he will never form an inter- 

 mediate race. But from the cases already given, and from 

 others which have been recorded; it appears that patience alone is 

 necessary ; as Mr. Spooner remarks, " nature opposes no barrier 

 to successful admixture ; in the course of time, by the aid 

 of selection and careful weeding, it is practicable to establish 

 a new breed." After six or seven generations the hoped-for 

 result will in most cases be obtained ; but even then an occa- 

 sional reversion, or failure to keep true, may be expected. The 

 attempt, however, will assuredly fail if the conditions of life 

 be decidedly unfavourable to the characters of either parent- 

 breed. 29 



Although the grandchildren and succeeding generations of 

 cross-bred animals are generally variable in an extreme degree, 

 some curious exceptions to the rule have been observed, both 

 with crossed races and species. Thus Boitard and Corbie 30 

 assert that from a Pouter and a Bunt " a Cavalier will appear, 

 which we have classed amongst pigeons of pure race, because it 

 transmits all its qualities to its posterity." The editor of the 

 'Poultry Chronicle' 31 bred some bluish fowls from a black 

 Spanish cock and a Malay hen; and these remained true to 

 colour "generation after generation." The Himalayan breed 

 of rabbits was certainly formed by crossing two sub- varieties of 

 the silver-grey rabbit ; although it suddenly assumed its present 

 character, which differs much from that of either parent-breed, 

 yet it has ever since been easily and truly propagated. I crossed 

 some Labrador and Penguin ducks, and recrossed the monorels 

 with Penguins; afterwards, most of the ducks reared during 

 three generations were nearly uniform in character, being brown 

 with a white crescentic mark on the lower part of the breast 



29 See Colin's ' Traite de Phys. Comp. 30 ' Les Pigeons,' p. 37. 



des Animaux Domestiques,' torn. ii. p. 31 Vol. i., 1854, p. 101. 



536, where this subject is well treated. 



VOL. IT. H 



