COAT CHARACTERS IN GUINEA-PIGS AND RABBITS. 73 



It is expected that one-fourth of the young will be albinos, and this 

 proportion is approximated. But all six of the albinos thus far ob- 

 tained have pigmented extremities, as did their Himalayan grand- 

 father. No pure whites have been produced. In this respect my 

 results differ from those of Raspail. It is true that the intensity of 

 pigmentation of these extracted Himalayans varies considerably, as 

 does that of the pigmented young. There are dark and light Hima- 

 layans, just as there are dark and light grays, among the offspring. 

 Cross-breeding has in this case, as in others, been the cause of variation 

 within the types of the parents, but I have no evidence as yet that it 

 can completely remove the pigmentation from the Himalayan albino 

 type, thus converting it into a pure albino. Nevertheless further ex- 

 periments may lead to this result, yet I hardly expect it in view of the 

 distinctness shown by the Himalayan and the pure albino types in the 

 experiments already described. I suspect, rather, that the Russian 

 female, with which Raspail began his experiments, was in reality a 

 hybrid, like those which I have described on page 70, in which pure 

 albinism was recessive. Raspail says concerning her, page 172 : 



La femelle de Lapin russe qui m'a servi pour mes experiences, n'e*tait pas de 

 race pure : le museau, I'extre'mit^ des pattes, les oreilles et le dessus de la queue 

 e*taient d'un noir moins franc et moins veloute'; sa taille etait notablement plus 

 forte et ses yeux rouges indiquaient qu'elle tournait a Palbinisme. 



This explicit statement and description certainly favors the idea that 

 she was a cross-bred with a pure albino race, which, if true, would 

 fully explain the occurrence of pure albinos in her offspring of genera- 

 tion F 2 , without necessitating the conclusion that the peripherally 

 pigmented type of albino had been transmuted into the unpigmented 

 type by cross-breeding. 



HEREDITY OF LONG OR "ANGORA" COAT. 



This character is in rabbits, as in guinea-pigs, a recessive Mendelian 

 character. Dominance and segregation both appear to be complete in 

 crosses between normal (or short-haired) and angora (or long-haired) 

 rabbits. I have observed in this case neither formation of intermediates, 

 i. <?., of inferior long-haired specimens, nor deviation from the expected 

 proportions of long-haired and short-haired individuals, of which con- 

 ditions there were some indications in guinea-pigs. But in one or two 

 cases I have thought that 1 could recognize in hybrids a greater soft- 

 ness of the coat, just as in guinea-pigs which are cross-breds between 

 long-haired and short-haired races. 



The numbers of young thus far reared are small, and not much 

 weight is to be attached to them, so far as quantitative results are con- 

 cerned. 



I 



