446 RUTH J. STOCKING 



alike in respect to normality or abnormality. That is, if the 

 progeny of the exconjugant a are abnormal, the progeny of 

 its mate b are more frequently abnormal than would be the case 

 if the distribution of abnormal races were not affected by con- 

 jugation. This is an example of what Jennings and Lashley 

 ('13) have called biparental inheritance as a result of conjuga- 

 tion. As these authors point out and as Dobell ('14) has recently 

 emphasized, this does not mean that the characters of the 

 progeny of the two exconjugants are known to resemble the 

 characters which the two parents had before they conjugated. 

 It means merel}^ that the characteristics of the progeny of a 

 are not determined by the nature of a alone, but partly also by 

 the fact that a has conjugated with h. Just what the resulting 

 similarity of the progeny of a and b should be called is of little 

 importance, as compared w^ith a clear grasp of the facts in the 

 case, yet it is perhaps worth while to point out that similar 

 relations often appear in what is called inheritance in higher 

 organisms. Two heterozygotic parents frequently produce prog- 

 eny which differ from both of them, yet what the progeny shall 

 be is determined by the constitution of both of the parents. 



6. We are dealing here with characters that are called abnormal. 

 What is the bearing of this on any conclusions drawn from this 

 study? Can we learn anything worth while from the study of 

 abnormal characters? 



What we can learn from abnormalities, and what the relation 

 of their behavior is to that of other characters can be deter- 

 mined only by investigation; the present paper *is offered as a 

 contribution toward answering such questions. But certain gen- 

 eral principles appear worthy of consideration. What is the 

 real status of the conception of abnormality? Does it mean 

 anything more than that the condition so characterized is not 

 the one usually found? It certainly does not mean that the 

 condition is one not subject to law of any sort. If we charac- 

 terize the course of inheritance of these characters as abnormal, 

 we can mean no more than that they do not follow the usual 

 course. But the course they do follow is one actually occurring 

 in animals, and therefore one not inconsistent with the nature 



