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THE AMERICAN NATURALIST 



[Vol. XLII 



itself in product, its significance in inheritance can not 

 well be overestimated. 



Xot only may physical features be accurately inherited, 

 but the capacity to perform various complex sets of ac- 

 tions may be transmitted with great precision. It is diffi- 

 cult if not impossible for us to state the exact source of 

 many of our modes of actions. We inherit much and we 

 learn much, and whether in a given complex act we are 

 dealing with an inheritance or a new acquisition or a 

 mixture is not always easy to state. With certain lower 

 animals this question is perhaps more readily decided. 

 Bees have the capacity of building a truly wonderful 

 structure, the comb, which, because of economy of ma- 

 terial and accuracy of workmanship, has long been an 

 object of admiration. Is this complex activity inherited or 

 learned by imitation? To answer this question, Kogev- 

 nikov reared some bees from a comb placed in an empty 

 hive. After the bees had hatched and got their strength 

 they proceeded without having seen other bees at work to 

 make a comb that was as perfect as one made under ordi- 

 nary circumstances. It might be objected that they had 

 seen the comb from which they themselves had hatched, 

 and this must be admitted to be so ; but this fact is prob- 

 ably without significance, for they made perfectly typical 

 queen cells the like of which they had never before seen. 

 It is thus evident that not only structural peculiarities but 

 highly complex activities can be inherited. 



The means of this inheritance has already in a measure 

 been made out. When a common protozoan, like Para- 

 mecium, reproduces, the parent body divides into ap- 

 proximate halves. Each of the two offspring receives not 

 only a large portion of the parental substance but a cer- 

 tain number of cilia and other parts directly from the 

 parent, and hence that the offspring should resemble the 

 parent is not very surprising. When, however, reproduc- 

 tion in the higher multicellular animals is examined a 

 somewhat different condition is discovered. Sexual re- 

 production is accomplished by means of a fertilized egg, 



