84 INHERITANCE. Chap. XIV 



mother conversely to her granddaughter. We thus learn, and 



the fact is an important one, that transmission and development 

 are distinct powers. Occasionally these two powers seems to be 

 antagonistic, or incapable of combination in the same individual ; 

 for several cases have been recorded in which the son has not 

 directly inherited a character from his father, or directly trans- 

 mitted it to his son, but has received it by transmission throuo-h 

 his non-affected mother, and transmitted it through his non- 

 affected daughter. Owing to inheritance being limited by sex, 

 we can see how secondary sexual characters may first have 



o 



» 



arisen under nature ; their preservation and accumulation bein 

 dependent on their service to either sex. 



At whatever period of life a new character first appear; 

 it generally remains latent in the offspring until a correspondin 

 age is attained, and then it is developed. When this rule fails, 

 the child generally exhibits the character at an earlier period 

 than the parent. On this principle of inheritance at corre- 

 sponding periods, we can understand how i 

 display from the germ to maturity such a marvellous 



of characters. 



Finally, though much remains obscure with respect to In- 

 heritance, we may look at the following laws as fairly well esta- 

 blished. Firstly, a tendency in every character, new and old, to 

 be transmitted by seminal and bud generation, though often 



s 



- 



counteracted by various known and unknown causes. Secondly, 

 reversion or atavism, which depends on transmission and 

 development being distinct powers : it acts in various degrees 

 and manners through both seminal and bud generation. Thirdly, 

 prepotency of transmission, which may be confined to one sex, 

 or be common to both sexes of the prepotent form. Fourthly, 



transmission, limited by sex, generally to the same sex in which 



the inherited character first appeared. Fifthly, inheritance at 

 corresponding periods of life, with some tendency to the earlier 

 development of the inherited character. In these laws of In- 

 heritance, as displayed under domestication, we see an ample 

 provision for the production, through variability and natural 

 selection, of new specific forms. 



