HEREDITARY INEFFICIENCY. 



303 



essentially alike for a period after their birth. The crab 

 continues and develops an active life. The Sacculina 

 thrusts its feelers into the body of the crab on which it 

 is to feed. Its organs of eating and swimming disap- 

 pear. All structures connected with independent life 

 become atrophied, and finally nothing is left of the Sac- 

 culina except its saclike body, its feelers or roots rami- 

 fying through the blood vessels of the crab, and its 

 reproductive organs by which the brood of parasites is 

 kept alive. When the habit of parasitism is once estab- 

 lished, the struggle for existence simply intensifies it 

 from generation to generation. 



The fittest Sacculina is the most degenerate one. In 

 like manner whenever a race or family of men has fallen 

 away from self-helpfulness the forces of evolution inten- 

 sify its parasitism. The successful pauper is the one 

 who retains no capacity for anything else. The loss of 

 all other possibilities is the best preparation for the life 

 of the sneak thief. 



Recent studies, as those of Dugdale, McCulloch, and 

 others, have shown that parasitism is hereditary in the 

 human species as in the Sacculina. McCulloch has 

 selected the Sacculina for special illustration of the 

 results of like processes in the human family. Like 

 produces like in the world of life. Those qualities in 

 the grandparent which made him an outcast from so- 

 ciety or a burden upon it reappear in the father and 

 again in the son. As in one case, so in the others, they 

 determine his relation to society. The pauper is the 

 victim of heredity, but neither Nature nor society recog- 

 nises that as an excuse for his existence. The forces of 

 Nature take no account of motive and are no respecters 

 of persons. Dugdale has shown that parasitism, pauper- 

 ism, prostitution, and crime reappear generation after 

 generation in the descendants of "Margaret, the mother 



