32 A TREATISE ON HORSE-BREEDING. 



that even variations produced by mutilation, or 

 by other artificial means, are sometimes trans- 

 mitted, especially when the mutilation has been 

 intimately' connected with the nervous system. 

 Dr. Prosper Lucas gives numerous well-authen- 

 ticated instances of this character, and is decid- 

 edly of opinion that variations or mutilations 

 that are the result of disease are transmissible. 

 That eminent scientist, Dr. Brown-Sequard, 

 gives an interesting account of some experi- 

 ments with guinea pigs. By an operation upon 

 a certain nerve he produced epileptic convul- 

 sions; and the produce of the animals upon 

 which this operation was performed manifested 

 the same symptoms.* But, notwithstanding 

 the numerous instances given by the eminent 

 authorities above quoted, I am of the opinion 

 that the cases of the transmission of these arti- 

 ficially produced variations are so rare as to be 

 practically of no account in the calculations of 

 the breeder. 



The law which governs the transmission of 

 these accidental variations, whether they be 

 the result of a "sport" or of external influences, 

 appears to be that when such variations from 

 the common type are in antagonism to the 

 conditions of life to which the individual is 



* 4 'Proceedings of the Royal Society of Great Britain," Vol. X, 

 p. 297. 



