312 E. UHLENHUTH. 



TABLE II. 



EXPERIMENT I.: 27 DAYS AFTER BEGINNING OF EXPERIMENT. 



Yet the influence of the iodothyrine on metamorphosis had become 

 noticeable in spite of the early stage of the larvae, as the gills as 

 well as the fin of the tail are found to be greatly atrophied. 



Experiment II. In this experiment one series of the embryos 

 of Ambystoma maculatum was kept in inorganic iodine and one in 

 iodine-free water. The concentration of iodine was i drop of a 

 1/20 M iodine solution per 1,000 c.c. of iodine-free water in the 

 beginning, was increased later on to 8 drops and then gradually 

 decreased to 3 drops. The embryos were at an early stage (for- 

 mation of neural folds), when the experiment started; only the 

 common jelly mass was removed. 



TABLE III. 



EXPERIMENT II.: 10 DAYS AFTER BEGINNING OF EXPERIMENT. 



TABLE IV. 



EXPERIMENT II.: 18 DAYS AFTER BEGINNING OF EXPERIMENT. 



i Several eggs and embryos were attacked by moulds and as they disin- 

 tegrated or developed abnormally, they had to be discarded causing thus the 

 decreases in the total numbers. 



