Production of Inherited Variations 203 



other hand the phenomena with which he deals are excessively 

 complicated and variable, making errors of interpretation 

 easy to one who is strongly convinced of a particular 

 doctrine, as Kammerer evidently is of the inheritance of en- 

 vironmental effects. Some results and interpretations re- 

 ported by him have put a strong strain on the powers of 

 acceptance of other investigators ; notably his report of 

 the inherited effect of cutting off a certain organ in the 

 ascidian ; 1 and his report that when the ovary of a given 

 sort of salamander is transplanted to the body of another 

 kind, the germ cells of this ovary transmit the characters of 

 the body to which they were transplanted. Kammerer's 

 work is distinctly in need of confirmation. 



Stockard dealt with the effects of alcohol on the germ 

 cells, and through these on the later generations of off- 

 spring in the Guinea pig. He found that continued ad- 

 ministration of alcohol to the parents so injures their germ 

 cells that their progeny and their descendants of later gen- 

 erations are weak, imperfect, diseased, deformed, in many 

 ways. 



Somewhat similar results had been reached years before by 

 Brown-Sequard (1869), in studying the results of mutilation 

 of the parent in Guinea pigs. Repetition of his work by 

 later investigators has not convinced students of the subject 

 that it was correctly interpreted; it is believed that he was 

 dealing with diseased stocks. The study made by Pearl 

 (1917 a) of the effects of alcohol in the fowl did not bring 

 to light any such results as Stockard's on the Guinea pig, 

 so that there is on the whole a tendency to suspend judg- 

 ment as to the interpretation of the results until Stockard's 

 work has been repeated on a new stock. 



Thus all along the line there is a feeling of uncertainty 

 1 See the comment of Castle^ 1916o, page 29, on this point. 



