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THE AMERICAN NATURALIST [Vol. XLVI 



produced by the same sire, whether he is mated with 

 dams of low or of high fecundity. 



9. High fecundity is not inherited by daughters from 

 their dam. This is proved by a number of distinct and 

 independent lines of evidence, of which the most im- 

 portant are: (a) continued selection of highly fecund 

 dams does not alter in any way the mean egg production 

 of the daughters; 6 (b) the proportion of highly fecund 

 daughters is the same whether the dam is of high or of 

 low fecundity, provided both are mated to the same 

 male; 7 (c) the daughters of a fecund dam may show 

 either high fecundity or low fecundity, depending upon 

 their sire; (d) the proportion of daughters of loiv fe- 

 cundity is the same whether the dam is of high or of low 

 fecundity, provided both are mated to the same male. 



10. A low degree of fecundity may be inherited by the 

 daughters from either sire or dam or both. 



11. The results respecting fecundity and its inherit- 

 ance stated in paragraphs 3 to 10 inclusive are equally 



•Pearl, E., "The Eelation of the Eesults Obtained in Breeding Poultry 

 for Increased Egg Production to the Problem of Selection," Ept. 30th 

 Meeting Soc. Proc. Agr. Sci., pp. (of reprint) 1-8, 1910; "Inheritance in 

 'Blood Lines' in Breeding Animals for Performance, with Special Eefer- 

 ence to the '200-egg' Hen," Ann. Ept. Amer. Breeders' Assoc., Vol. 6, 

 pp. 317-326, 1911; "Inheritance of Fecundity in the Domestic Fowl," 

 Amer. Nat., Vol. 45, pp. 321-345, 1911; "Breeding Poultry for Egg 

 Production," Me. Agr. Expt. Sta. Ann. Ept. for 1911, pp. 113-176. Pearl, 

 E., and Surface, F. M., "Data on the Inheritance of Fecundity Obtained 

 from the Records of Egg Production in the Daughters of '200-egg' Hens," 

 Me. Agr. Expt. Sta. Ann. Ept. for 1909, pp. 49-84 (Bulletin 166), 1909; 

 "Studies on the Physiology of Reproduction in the Domestic Fowl. IV. 

 Data on Certain Factors Influencing the Fertility and Hatching of Eggs," 

 Me. Agr. Expt. Sta. Ann. Ept. for 1909, pp. 105-164, 1909; "A Biometrical 

 Study of Egg Production in the Domestic Fowl. I. Variation in Annual 

 Egg Production," U. S. Dept. Agr., Bur. Animal Ind. Bulletin 110, Part I, 

 pp. 1-80, 1909; "A Biometrical Study of Egg Production in the Domestic 

 Fowl. II. Seasonal Distribution of Egg Production," Ibid., Part II, pp. 

 81-170, 1911. 



1 This is true, of course, only for certain gametic types of low fecundity 



ThT s aI iTmitL wi11 l e clear t0 any one wh0 has studied the detailed evidence - 



evidence in favor of the conclusion standing at the beginning of paragraph 9. 



