PLATE 17 



EXPLANATION OP FIGUltKS 



55. Photographs of a normal and an albinous frog tadpole to show the xantho- 

 leuoophores. Photographed May 26th. The same specimens as shown in figure 44. 



X7. 



56. An enlargement of a portion of the dorsal body surface of the specimens 

 shown in figure 55. 



146 



