84 MR. W BATESON ON COLOUR-HEREDITY [May 26, 



Hating. Offspring. 



(34) bl. 9 D2(D X «) (DR) X bl w. <? a (DR) 2 bl. 1 br. 2 blw. 



(35) „ X w. (? e 1 bl. 1 br. 3 bl^w. 2 w. (4 eaten). 



(36) „ Xbrw.(?C2-2(DD)(C2xa) 3bl. 2 br. 1 blw. (3 eaten). 

 (37)br.?D^(DX«)(DR)Xbhv.c?a(DR) 2 bl. 1 br. 3w. 



(38) „ Xbrw.,?-)' (DR) 3 br. 2 brw. 3w. 



(39) „ Xw.(?e 1 bl. 1 blw. 1 brw. 2 w. 



(40) w. ? B2-1 (B2 X a) X blw. $ a (DR) ... 2 blw. 3 w. (3 eaten). 



(41) „ X „ ... ow. 



(42) blw. ? Ci-2 (Ci X a)(DR) X blw. $ a (DR) ... 7 blw. 



(43) „ X ;, ... 4 blw. 2w. 

 (44)blw.?Ci-3(CiX6)DRx brw.3^7(BXa)(DR) ... 7 blw. Iw. 

 (45) blw.?D2-3(D2xa) Xblw.^a(DR) ... 5 blw. 

 (46)blw.?D3-3(D3xa) X brw. <?C2-2(C2xa)(DD) 1 bl. 1 br. 1 blw. (1 died). 



(47)bl.?Di-i(DiXa)(DR)X w.(?6 1 bl. 2 blw 2w. 



(48)blw.?Ci-2-i(Ci-2Xo)X blw.<?a(DR) ... ... 5 blw. 



(49) blw.?Ci-2-2(Ci-2xa)X blw.(?a(,DR) ... ... 7 blw. 



(50)blw.?Ci-2-2-i(Ci-2-2xa)Xblw.<?a(DR).. ... 4 blw. 



The mice originally introduced were 5 albino females, 2 albino 

 males, 1 black-and-white male, and 1 black-and-white female, all 

 of unknown extraction. 



Several albinos were produced in the experiments. Mated with 

 albinos they gave albinos only (41 in all). The original blw. S a was 

 heterozygous, containing albino, but the blw. 5 C probably did not, 

 though the figures are insufficient for proof. Both of the original 

 blw, on mating with albino gave rise to some hroimi or brown *- 

 and-white off'spring, and were probably giving off" gametes of 

 this nature. All such specimens were alike in tint except one 

 which was distinctly lighter. 



The families of the albino D (expts. 10-14) are especially 

 interesting ; for, as Mr, Parsons pointed out to me, all the 1 3 

 coloured offspring by two different 6ro^e7i- coloured males, one brw,, 

 the other blw., were seZ/'-coloured, brown, or black. This result 

 resembles one obtained by Castle (6, p, 542), but the suggestion 

 that such a pied individual is a mosaic which throws self-colour 

 gametes is not readily applicable to this case. For hei'e the 

 peculiarity evidently lies in the gametes of the individual albino, 

 since with other albinos the same males gave pied offspring-. As 

 Castle commonly obtained such self-coloured mice from albinos 

 crossed with pied, it is likely that the peculiarity may belong to 

 certain strains of albinos. The detailed account of his experiments, 

 which is promised, may perhaps give an indication on this point. 



Parsons' cases give besides some indications as to the ratios of 

 the gametes. It will be seen that the relation of brown to black 

 is not merely that of dominant and recessive, for either may give 

 either. Nor can it be supposed that the brown is a mere hetero- 

 zygous form. Each colour, whether self or pied, may be 

 dominant over albino, and the figures show pretty clearly that in 



* Microscopical examination of a specimen kindly sent by Mr. Parsons proved 

 tliis colour to be " chocolate." 



