Observations of July 5. 



Thyroidless iodine-fed. 



Culture 1 . 



2. 

 3. 

 4. 



Normal iodine-fed. 



Culture 1 



Thyroidless control . 

 Normal 



Total 

 length. 



Hind 

 legs. 



Fore legs. 



Tail 

 atrophy. 



Condition. 



Completed metamorphosis, June 25 to 29. 



33.0 

 34.5 

 33.0 



11.5 

 6.0 



4.5 



Through.* 



+ 



Emaciated. 



Completed metamorphosis, June 12 to 18. 

 " " " 18 " 23. 



" 28 " July 5. 

 Thin. 



Mortal- 

 ity. 



* Fore limbs through skin in three animals of thyroidless Culture 2 ; culture 

 began metamorphosing July 3 and completed the transformation by July 10. 



Observations of July 19. 



Thyroidless iodine-fed. 



Culture 1. 



2. 



3. 



" 4. 



Normal iodine-fed. 



Culture 1 . 

 " 2. 



Thyroidless control. 

 Normal 



Total 

 length. 



Mortal- 

 ity. 



Completed metamorphosis, June 25 to 29. 

 July 3 " 10. 

 38.0 

 37.0 



Completed metamorphosis, June 12 to 18. 

 " " " 18 " 23. 



" 28 " July 5. 



Observations of July 30. 



Thyroidless iodine-fed. 



Total 



length. 



Completed metamorphosis, June 25 to 29. 

 July 5 " 10. 

 43.0 

 40.0 



Mortal- 

 ity. 



Completed metamorphosis, June 11 to 18. 

 " " " 18 " 23. 



" 28 " July 6. 

 July 27 " August 2. 

 1 

 1 



166 



