393 THE POPULAR SCIENCE MONTHLY. 



process of their extinction might be initiated by an artificial ste- 

 rility. Such a measure would be impracticable, because it would 

 be impossible to fix a limit; and it would certainly be ineffica- 

 cious in proportion as the temperaments of the persons concerned 

 should be averse to their submission to the laws. The contest 

 may be made by less uncertain processes. 



Restoration of a degenerated race return to mediocrity, as 

 it has been called may be effected through crossing with indi- 

 viduals of healthy races. M. Sanson has shown, by good exam- 

 ples drawn from zootechny, that heredity of biological character- 

 istics, and even perhaps of the sex, is generally influenced by the 

 condition of nutrition of the progenitors. The stronger of them 

 attracts the resemblance to his side. It may be assumed that in a 

 union including a morbid factor the healthy factor is in the bet- 

 ter position to prevail, and all the more so because it has the 

 atavistic tendency of the other side in its favor. But whether 

 because of the rarity in our time of absolutely healthy elements, 

 or for some other reason, we usually find that, in crossing, the 

 good are more likely to lose than the bad to improve. 



There are still other means than happy crossing that may 

 help in the return to mediocrity. Less and less deficient children 

 may be observed to be born in a family of degenerates as the 

 biological conditions of the parents improve. There is nothing 

 surprising in the fact that disorders of nutrition have an injuri- 

 ous influence ; all improvements of nutrition may, on the other 

 hand, be accompanied by a correlative amelioration of the prod- 

 ucts. Generation is, as a whole, the resultant of an excess of 

 nutrition ; the lower organisms, absorbing in the medium in 

 which they live more elements than they need for the repair of 

 their losses, increase in volume. When this increase exceeds a 

 certain limit, the individual breaks itself up to form new beings. 

 The process is much more complex in the higher animals, but it 

 is fundamentally the same ; and Haeckel has felt free to call 

 reproduction the excrescence of the individual. The best condi- 

 tions for generation are the best conditions of nutrition. To the 

 regularity of their nutrition is due the regularity of the fold- 

 ing of blastodermic leaflets and the regularity of their further 

 evolution. The arrest of development of a single cell in the ear- 

 lier periods of evolution is susceptible of determining grave de- 

 formations. 



Facts observed in human families, in which we see degen- 

 erates producing offspring less and less deficient as their own 

 conditions of nutrition improve, indicate that under the influence 

 of a superactivity of nutrition defective organisms might furnish 

 a normal epigenesis. Further, the possibility of combating dur- 

 ing the embryonary period the degenerative tendency which is 



