296 THE CROSSING, AC, OF PIGS. 



before sterility and completely shattered constitutions, 

 are threatened. When these effects occur, the animal 

 is required again to be crossed, to preserve it ; and that 

 tolls the knell of the old breeds, and rings in the 

 advent of a new breed. When the individuals of this 

 new breed, become, by interbreeding, of a dead uni- 

 formity of character, they must repeat the same process, 

 and their breed undergo a complete metamorphosis. 

 Were the characters, which are reduced in these breeds, 

 all developed, th'e breeds might run their course, for 

 centuries, without being driven to a cross. Or, did 

 breeders give the legs a little shoWj they would not 

 be forced to the unpleasant necessity of so frequently 

 crossing their choice breeds. 



Darwin says (page 120, Vol. ii, Animals and 

 Plants, &c): 



"The improved Essex Pig owes its excellence to 

 repeated crosses with the Neapolitan, together, proba- 

 bly, with some infusion of Chinese blood." 



The advantage of crossing with the Neapolitan, and 

 with Chinese breeds, is due to the fact, that the Nea- 

 politan and Chinese standards do not require the # 

 reduction of so many characters, as does the English 

 standard of Pig breeding. 



" With most of the improved races of the Pig," says 

 Darwin (p. 120, Vol. ii, Animals and Plants, &c), 

 "there have been repeated crosses." 



He says, that, owing to the great delicacy of consti- 

 tution, and to the sterility entailed upon highly-bred 

 animals, a great amount of crossing has been found 

 necessary, to keep the breeds from extinction. 



