RELATION OF lODIN TO THYROID 



409 



TABLE 8 



An attempt was made to see if feeding iodin had the same effect 

 upon the gut. A series of larvae appropriately controlled was 

 started upon the iodin diet to test this matter. The animals 

 were fed iodin for twenty days. Table 9 shows the effect upon 

 the gut at the end of this interval. 



3. Experiments with feeding iodoform to normal larvae 



An experiment similar in all respects to the potassium iodide 

 and iodin feeding was carried out in which iodoform and flour 

 was used' as food. The proportions of flour and iodoform used 

 was the same as described for the other experiments. Iodoform 

 appears to have a marked effect in accelerating metamorphic 

 changes in frog larvae, although the reaction is not so rapid as 

 when iodin crystals are used. The iodoform is toxic for the 



