REPRODUCTIVE PROCESS IN ANIMALS 65 



the zygote undergoes its very first fission into two cells 

 one of the two is seen to be already marked off as the 

 somatic cell from the other which remains as gonad. 

 The gonad is in fact simply a set aside portion of the 

 substance of the zygote, in other words a persisting 

 portion of the gonads of the two parents. 



The fact that the gonad is not produced by the indi- 

 vidual in whose body it lies, but is rather a persisting 

 portion of living substance handed on from the previous 

 generation and living its own life within the surrounding 

 soma, is of great practical importance, for it renders less 

 mysterious the fact that what are called acquired characters, 

 or better impressed characters, are not inherited. If the 

 soma or body has any striking modification impressed 

 upon it during its lifetime say a scar produced by 

 disease or injury, or the loss of a limb this feature is 

 not handed on to the next generation. It is one of the 

 few comforting reflections during this horrible war, when 

 we so often see those dear to us maimed for life, that at 

 least these injuries do not register themselves in the 

 gonad so as to be passed on to the generation to come. 

 And this fact ceases to be surprising when we remember 

 that the gonad is not produced by the individual in whose 

 body it is contained, but is a heritage from the generations 

 that have gone before. 



S.H. 



