IOO 



Experimental Zoology 



314 young, all pigmented ; and these last give in later generations 

 some albinos. The results agree fairly closely with Mendelian 

 expectations. 



Castle has found, as had Allen and Cuenot for mice, that 

 albinos, although breeding true, may carry latent or suppressed 



FIG. 7. Upper figure, short-haired, smooth coat red guinea pig. Lower figure, 

 long-haired, rough coat albino. (After Castle.) 



colored characters. Thus one albino individual, a male, when 

 mated with red females produced offspring marked with black. 

 Another albino crossed with the same and with other red females 

 gave young marked with black and red in about half the cases, 

 the other half showing only red or yellow, but no black. A third 

 albino mated with red females produces only red or yellow 

 offspring, never black ones. In the light of these results, Castle 



