MODIFICATION OF THE GERM-CELLS IN MAMMALS 121 



were mated with normal females, the individuals resulting from 

 such matings were as a group decidedly inferior to the young 

 produced by normal females when mated with control males. 

 This group inferiority was not only present in the grandchildren, 

 or F2 generation, but also in the F3 generation descended from 

 alcoholized great-grandparents. 



Fortunately, since these experunents were first reported, sev- 

 eral similar studies by other investigators using the methods here 

 employed have been conducted on other mammals and birds. 



Our results have been corroborated, though the response to the 

 treatment has in some instances been thought to differ from that 

 shown by the guinea-pigs. Useful and suggestive interpretations 

 of the results have been advanced, yet certain points of view are 

 presented with which we are not always able to completely agree. 

 The bearing of these studies on the present results will .be dis- 

 cussed in a section beyond. 



In particular we are indebted to Pearl ('17) for his recent 

 characteristically clear and exact analysis of the influence of 

 alcohol fumes on domestic fowls and their progeny. This study 

 has suggested to us the unportance of a considerable amount of 

 data contained in the card-catalogue records of our animals which 

 had not been fully valued in the previous discussions of the ex- 

 periments. In the present report we have followed several of 

 Pearl's ideas in more completely separating the qualities to be 

 contrasted between the alcoholic and control lines. 



As might be expected, various objections have been advanced 

 from time to time regarding the cause and explanations of the 

 results which we have reported on the effects of alcohol in the 

 guinea-pig. In all cases, however, the objections have been 

 raised either by persons entirely unfamiliar with these animals 

 and their breeding qualities or by others who have not been 

 sufficiently interested or careful to read the descriptions of the 

 animals and breeding methods used. It has been suggested on 

 certain occasions that the defects and degenerate conditions 

 which have been reported in our alcoholic lines were probably 

 present in the original stock on which the experiment was con- 

 ducted. Such a remark in the face of the experimental control 



