178 Inheritance of Coat Colour in Mice 



This evidence is perfectly consistent with the scheme which I 

 previously published (3) expressing the relations of black, chocolate, 

 blue, silver fawn, to each other, and shows conclusively that Cu^not's 

 representation of chocolate as a dilution form of black is incorrect. 



Finally I wish to record the result of mating agoutis together 

 heterozygous in black. The results should yield a ratio of 3 to 1, but 

 my numbers are not in accordance with this ratio. 



I obtained 76 agouti, 37 blacks. 



The agoutis which result from mating agouti with black are much 

 darker than the ordinary agouti and very often there is a markedly 

 dark streak down the middle of the back. 



The expenses of these experiments were partially defrayed by a 

 grant from the Royal Society. 



REFERENCES. 



(1) Hagedoorn, Archiv Entwickelungsmeckanik, Vol. xxviii. 1909. 



(2) Cu^NOT, Arch, de Zool. Exp. et Gm. Vols. i. ll. lii. vi. 



(3) Durham, Report IV. Evolution Committee Royal Society. 



(4) Plate, Festschrift zum 60 Gehurtstage Richard Hertwig, Bd. ii. 191. 



(5) Castle, Science, N. S., Vol. xxxii. 1910. 



(6) Darbishire, Biometrika, Vol. ii. 1903. 



(7) Baur, Ber. Deutsch. Bot. Ges. xxv. 1907. 



