66 INHERITANCE IN RABBITS 



Plainly it is unprofitable to attempt to find illustrations of all these con- 

 ceivable variations. We shall content ourselves with noticing some of 

 the more important varieties of albinos and presenting evidence that each 

 of the 4 variable factors, A, E, I, and U, is transmitted through albinos. 



The foUovv^ing albino varieties may be expected to occur: 



(i) White producing gray only (in crosses with any pigmented variety); for- 

 mula, BjBrjEjAjIjUjYj. 



(2) White producing black only (in crosses with black or any pigmented variety 



recessive to black); formula, BjErjEjIjUaYj. 



(3) White producing yellow only (in crosses with yellow or sooty individuals) ; 



formula, BjBrjRjAjIjUjYg. 



(4) White producing sooty only (in crosses with sooty) ; formula, BoBrjRjIzUjYj. 



(5) White producing gray, and black (in crosses with black or any pigmented 



variety recessive to black); formula, BjBrjEjATjUjYj. 



(6) White producing gray, and yellow (in crosses with yellow or sooty) ; formula, 



B2Br3E(R)A2l2U2Y2. 



(7) White producing gray, black, yellow, and sooty (in crosses with sooty) ; 



formula, B2Br2E(R)Al2U,Y2. 



(8) White producing black, and sooty (in crosses with sooty); formula, 



B2Br2E(R)l2U2Y2. 



(9) White producing yellow, and sooty (in crosses with sooty); formula, 



B2Br2R2Al2U2Y2. 



Another set of 9 varieties, quite similar to these, w^ould produce only 

 pale-pigmented offspring. As regards the intensity factor they would 

 be D2 instead of I2. Another set of 9 varieties would produce both dilute 

 and intensely pigmented offspring, being heterozygous, 1(D), as regards 

 the intensitv factor. 



Nine other varieties, in which S2 replaces U2, would produce only spotted 

 young; and another set of 9 would produce both spotted and self-colored 

 offspring; in these U(S) would replace U2. Another set of 9 varieties 

 would produce only pale-pigmented spotted individuals, another would 

 produce pale-pigmented individuals, both self and spotted; and lastly a 

 set of 9 varieties would produce both dilute and strongly pigmented indi- 

 viduals, both spotted and self-colored. 



It is probable that the foregoing list of 72 varieties could be duplicated 

 in varieties having the Himalayan modification, and duplicated a second 

 time in varieties heterozygous in the two sorts of albinism. 



A few examples will now be mentioned of some of the 9 varieties of 

 albinos first enumerated, or of animals differing from those 9 varieties 

 in one or two characters only. 



Variety i is represented in our s 1425, which when mated with black 



9 1 541 produced 11 young, all gray, and when mated with yellow 9 547 



(variety 3) produced 4 young, all gray. Variety 2, but heterozygous in 



the Himalayan modification, C, and in spotting with white, U(S), is rep- 



