54 



THE AMERICAN NATURALIST 



own embryonic development she shows some sign or 

 weakness at her period of reproduction, or, that the 

 grandchildren are affected by the influence of alcohol 

 upon their grandpa rents. However, only one experi- 

 ment alone like the above is not sufficient to prove any- 

 thing, and furthermore, Hodge in speaking of dogs says : 

 "We do not attach much importance to the greater per- 

 centage of deformity, since this is of somewhat common 

 occurrence in kennels." 



If the transmission of an alcoholic weakness to subse- 

 quent generations is possible in any living organism, it 

 ought to be actually demonstrated in some manner, but 

 if it is a delusion, the sooner it is dispelled the better. 

 These experiments with Hydatina sent a are an attempt 

 to determine, in one race of animals only, whether cer- 

 tain alcoholic weaknesses are truly hereditary and the 

 evidence found is negative. 



It by no means follows that these results would be 

 found to be true in man. Alcohol primarily affects the 

 nervous system and may have a very different action on 

 the highly organized nervous system of man than it does 

 on the lowly organized Hydatiua, whose nervous system 

 is extremely simple. Furthermore, the germ substance in 

 man is probably very different from the germ substance 

 in the rotifer and alcohol might have a very different 

 effect upon it. 



Summary 



1. Four strains of parthenogenetic rotifers originally 

 descended from the same female were observed throughout 

 twenty-eight successive generations. One strain was kept 

 as a control and the other three strains were kept in a 

 I per cent., a \ per cent, and a 1 per cent, solution of 

 alcohol. The rate of reproduction was lower in the alco- 

 holic strains than in the control and it was proportion- 

 ally lowered according to the amount of alcohol used. 



2. The individuals of the 1 per cent, alcoholic strain in 

 the XI-XV generations showed a decidedly increased 

 susceptibility to copper sulphate. 



