A. Figure on left: Japanese turtle "' mutant " No. 108 and mate No. 433. These are the parents of the other 



birds shown on this plate. The whitened "mutant" parent is shown to the left; the normal mate to 

 the right. 



B. The first two partial "mutants " and an intervening normal young from the parents noted above. 



C. The last three " mutant " offspring of "mutant " No. 108 and normal No. 433. 



