No. 579] ALBINO SERIES OF ALLELOMORPHS 147 



which yellow is completely inhibited, while black is only 

 slightly affected. 



Finally the question is raised whether anything similar 

 to this can be found among other mammals. Albinos are 

 found in many mamma ls as well as in lower animals. As to 

 multiple allelomorphs, the case of the Himalayan rabbit 

 is well known and compares well with the guinea-pig 

 series. The Himalayan rabbit with its pink eyes and 

 white fur with dark patches on nose, ears and feet is com- 

 parable to the guinea-pig albino. The complete albino 

 rabbit recessive to the Himalayan is lower in the series 

 than anything known in guinea-pigs. The dilution of the 

 blue rabbit as well as that of the blue mouse and maltose 

 cat is of a different type from the guinea-pig dilution. 

 As Miss Sollas has shown, the pigment is clumped in- 

 stead of uniformly decreased in quantity. The effect is 

 slate-blue instead of sepia-brown. Mr. H. D. Fish has 

 made crosses (unpublished data, to which T refer with his 

 permission) which show as expected that rabbit dilution 

 is inherited wholly independently of albinism. 



In man, we have albinos which are probably comparable 

 to guinea-pig and rabbit albinos. A study of the enor- 

 mous collection of data in the Monograph of Pearson, Net- 

 tleship and Usher convinces one that albinism in man is 

 recessive. But as Pearson points out, there are many 

 grades of albinism and each grade tends to maintain its 

 identity in inheritance. Among negroes there are albinos 

 with blue irises, red pupils, white skin and nearly white 

 hair. There are also darker grades, as with brown skin, 

 eyes and hair. There is no sharp line anywhere between 

 the complete albinos and the so-called xanthous types. 

 In the white races albinos pass into the extreme blonds in 

 a continuous series. In fact, study of records convinces 

 one that in some cases the same factor may produce well- 

 marked albinism, with red eyes, nystagmus and photo- 

 phobia in one member of a family, but merely extreme 

 blondism in another. It is worthy of note that human 

 light hair resembles closely the sepia of dilute guinea- 



