ii8 ARE THE EFFECTS OF USE INHERITED? 



improved or deteriorated habits and thoughts are 

 transmitted by personal teaching and influence and 

 are cumulative in their effect. But all this must 

 not be confounded with the inheritance of ac- 

 quired characters. Cases of quasi-inheritance 

 may perhaps be most readily distinguished from 

 cases of true inheritance by the time test. When 

 a modification acquired in adult life is promptly 

 communicated to the child in early life or from 

 birth, it may rightly be suspected that the in- 

 heritance, like that of money or title, is not truly 

 congenital, but is extraneous or even anti-con- 

 genital in its nature. Judged by such a standard, 

 the inherited injuries in Brown-Se"quard's 

 guinea-pigs are only exceptional cases of quasi- 

 inheritance, and are not necessarily indicative 

 of any general rule affecting true inheritance. 



