COAT CHARACTERS IN GUINEA-PIGS AND RABBITS. 



39 



A means of testing the validity of this explanation has been suggested 

 by Allen ( : 04) for the similar case of chocolate pigmentation in mice. 

 If the albino gametes which contributed to the production of the red or 

 yellow offspring in the matings last mentioned were really free from 

 black, then two of these hybrid red animals (containing recessive albin- 

 ism) when mated should produce albino offspring not anyot whose gam- 

 etes contain latent black. Experiment has shown this to be the actual 

 result. Albino ^ 1999 was produced by mating two hybrid yellow 

 animals containing recessive albinism. He has been several times 

 mated with yellow females (see Table F) and has produced 13 pig- 

 mented offspring, all yellow. As a control he was mated also with a 

 black female containing recessive albinism. This mating produced 

 3 albinos and i black pigmented young. Another albino tested, 

 $ 2059, is apparently similar in nature to J* 1999, for when mated 

 v/ith red 9 610, he produced 3 young, all red pigmented (see Table F) . 

 The ancestry of this albino is unknown to me, as I obtained him from 

 a breeder, and as no other test of this sort was made in his case, the 

 result can not be considered conclusive, because of the small number of 

 young produced ; but it is probable that all his gametes were free from 

 latent black, for four of his albino daughters by albino mothers con- 

 taining latent black form albino gametes free from black, as well as 

 other gametes containing black. They are 99 1216, 1222, 1224, 

 and 1236, Table E. Each of these four daughters of c? 2059, all that 

 have been tested, must have received from the father albinism free 

 from latent black, for the mothers, as stated, did not form gametes 

 containing latent black. 



TABLE F. Matings of albinos (not any of whose gametes transmit latent black) 

 with red or yellow animals. Not any of the offspring are black pigmented. 



