No. 523] NOTES AND LITERATURE 



137 



Case 2. — A young Himalayan (albino) female rabbit was 

 treated with lecithin and mated with a black male. She pro- 

 duced by him three litters of young. The first litter contained 

 six young, all black. The second litter contained four young, 

 two of which wen 1 Himalayan, two yellow-and-white. 7 The third 

 litter contained seven young, concerning the color of one of 

 which no account is given -, four were Himalayan, one yellow- 

 and- white and one black-and-white. The case (a selected one) 

 is supposed to show that continued treatment with lecithin pro- 

 duces more young of the maternal type in later than in earlier 

 litters. But a schctal cast can not fairly be used to show any- 

 thing of the sort. Only a fairly uniform result of repeated 

 experiments could establish it. ruder the circumstances we 

 can only ask what the expected Mendelian result would be in a 

 case like this if no lecithin treatment were involved, and then 

 inquire whether the observed result differs in any respect from it. 



If no lecithin treatment were involved we should say that the 

 black male used was heterozygous in the recessive characters 

 albinism, spot t inn' and yellow ; and the expectation would be that 

 he would produce young of five sorts in one of the following 

 distributions, depending on the gametic character of his albino 



The observed distribution for the three litters is 6:0:1:3:6. 

 This is so good a Mendelian result that it would not call for any 

 special comment in ordinary breeding work. Further matings 

 would be called for, but it would be surprising if these did not 

 supply the missing class, yellow, and give numbers agreeing more 

 closely with one or another of the suggested ratios. 



No control matings of either parent in case 2 are recorded 

 by Russo. 



