METAMOKPHOSIS OF AMPHIBIAN ORGANS 



261 



appeared fourteen days earlier than in experiment 40, and in 

 experiment 40 it became distinct twelve days after the isolation 

 into spots had started in experiment 39. The development of 

 the spots of experiment 40 occurred simultaneously in host and 

 graft ; in experiment 39 the graft was a spotless piece of skin and 

 comparison of the development of the spots was impossible. 



This case is perfectly clear as to network development. It 

 developed simultaneously in each graft and its host, but twenty- 

 one days earlier in graft and host of experiment 46 than in graft 

 and host of experiment 45. The development of the spots how- 

 ever, seems confused at the first glance in both experiments. 

 In experiment 45 the host developed its spots 11 days after the 

 spots of the graft had developed. We have already mentioned 



