254 ROMMEE AND PHILLIPS— INHERITANCE IN October 19, 



The decrease from .1088 to practically zero (.0032) from the 

 first to the fifth year does not necessarily mean that the inheritance 

 of fecundity is lost as a sow grows older, but probably indicates that 

 inheritance from the first dam gradually plays relatively less and 

 less of a part in the determination. So many other factors, body 

 strength, maturity, and functional habit, can influence this, that the 

 inherited tendency seems to lose its influence. The average for five 

 vears (.06) is, however, large enough to be of value to the breeder, 

 and with the large numbers here used (6145) the probable error is 

 small (.0086), and our results more nearly a true statement of the 

 conditions of inheritance. 



The authors wish to acknowledge courtesies shown in the prepa- 

 ration of this paper by Dr. C. B. Davenport and Mr. F. E. Lutz 

 of the Station for Experimental Evolution of the Carnegie In- 

 stitution. 



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