84 Inheritance of Melanism, in Tephrosia (Ectropis) 



like, or by some trivial alterations in the constitution of its sidechains, 

 has been so changed as to initiate different reactions in the building 

 up of the F^ insects — a conclusion differing in terms but essentially 

 the same in effect as that deduced from other considerations. Again 

 it simply amounts to stating that, in crosses, the genes or determiners 

 for unit characters are liable to undergo modification. 



To sum up, the results of our research are as follows : 



(1) In crosses within the limits of the species Tephrosia crepuscu- 

 laria the inheritance of melanism proceeds on ordinary Mendelian lines ; 

 this is in complete agreement with the work of Onslow and myself in 

 Tephrosia consonaria and Boarmia consortaria. 



(2) This character in interspecific crosses between Tephrosia cre- 

 puscularia and T. histortata behaves in a vastly different fashion. 



(3) From the indications of the last set of experiments one can only 

 conclude that unit characters may be changed during such crosses. 



(4) If the last statement be true (and there appears no alternative 

 to admitting its truth), then the possibility of modifying such characters 

 by other agents cannot be excluded. 



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■ and Hadley, P. B. "The English Rabbit and the Question of Mendelian 



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