PRINCIPLES AND PRACTICE OF BREEDING. 107 



parent transmitted a portion of all the properties, or a trait 

 here and a trait there, as chance or some special and 

 independent power in each animal to " mark " its offspring, 

 might dictate. An English gentleman by the name of Orton, 

 broached the theory that the animal organization is trans- 

 mitted by halves, the sire giving to the progeny the external 

 organs and locomotive powers, and the dam the internal 

 organs and vital functions. By this division, the general 

 form, the bones, the external muscles, the legs, skin and wool 

 would be like those of the male parent, while the heart, lungs 

 and other viscera, and consequently those functions on which 

 the integrity of the constitution mainly rests, would he like 

 those of the female parent. But each parent was supposed by 

 him to exert a degree of influence on the parts and functions 

 chiefly inherited from the other parent; and this law "of 

 limitations" he considered "scarcely less important to be 

 understood than the fundamental law itself." 



Mr. Walker, in his work on Intermarriage, presents the 

 same theory, substantially, except that he denies that the 

 series of organs inherited from one parent are modified or 

 influenced by the other parent ; and he assumes that between 

 parents of the same breed, "either the male or the female 

 parent may give either series of organs."* 



Mr. Spooner, in an article on Cross-Breeding, which appear- 

 ed in the Journal of the Royal Agricultural Society of England 

 some years since the publication of his well known work on 

 Sheep, adopts the Ortonian theory with some slight modi- 

 fications. He says: "The most probable supposition is that 

 propagation is done by halves, each parent giving to the 

 offspring the shape of one-half of the body. Thus the back, 

 loins, hind quarters, general shape, skin and size follow one 

 parent ; and the fore quarters, head, vital and nervous 

 system, the other ; and we may go so far as to add, that the 

 former, in the great majority of cases, go with the male parent 

 and the latter with the female."f 



The Ortonian theory, or either of the above modifications 

 of it, if actually carried into practice, would lead to singular 

 results. According to Mr. Orton, the effects of cross-breeding 

 would, comparatively speaking, stop with the first cross, for 

 each succeeding generation of cross-bred males and females 

 would continue to transmit to their descendants substantially 



* Vide pp. 142, 145. 



t Journal of Royal Agricultural Society of England, 1859. 



