PARENTAL ALCOHOLISM AND THE PROGENY 293 



This result means that as the duration of treatment in days 

 before hatching increases the proportion of germ cells falling in 

 the A' class increases. Comparing with controls as a base this 

 further means that this change is at the expense of the cells in 

 the a class. 



The percentage of fertile eggs hatched, the mortality of the 

 offspring, the weight at hatching and the growth to adult weight 

 are all superior in the progeny of alcoholists. These facts 

 argue very strongly in favor of the present hypothesis in general, 

 and in particular that part of it which postulates a group of 

 germ cells a' which are of such high physiological vigor as to 

 be effectively beyond the range of the selective agent acting at 

 intensity P. If in respect to one or two only of these charac- 

 ters were the alcoholists' offspring superior we might attribute 

 the result to accident. But when the whole series shows the 

 same thing such an explanation is out of court. No sensible 

 person would argue that the alcohol benefited the germ cells over 

 so long a period of time. A selective action of the sort here 

 postulated seems the only reasonable explanation of the objec- 

 tive experimental facts. It is known that an immediate, but 

 transitory, stimulating effect may follow the administration of 

 very minute doses of substances which in higher dosages act 

 as poisons. This was shown to be the case by Braconnot, work- 

 ing about the middle of the last century on the effect of various 

 substances upon the sensitive plant Mimosa. Czapek (5, p. 883) 

 in commenting upon Braconnot's result especially mentions that, 

 in spite of its potentially great importance, no later investigator 

 has systematically followed it up. Prof. C. M. Child informs 

 me that he has obtained exactly the same kind of a result in 

 his studies on the effect of such substances as KCN and alcohol 

 upon planarians. In the case of the present experiments, how- 

 ever, it could hardly be maintained that this primary stimu- 

 lating effect of a dilute poison would continue regularly and 

 constantly to appear after the poison had acted on the same 

 individuals continuously for months! For such a supposition 

 there appears to be no warrant in any known biological facts. 



