METAMORPHOSIS OF AMPHIBIAN ORGANS 273 



possessed truly larval characteristics: their gills and fin were of 

 enormous size, the color of the skin was still yellowish and the 

 melanophores had not yet formed any definite pattern. 



All animals were kept, before and after operation, in a cool, 

 dark room at an average temperature of 15°C. 



2. The results 



Among the seven experiments of series XXVI only five were 

 made in the manner described above; in some of them the eyes, 

 in others the skin, and in still others both of these organs were 

 examined. Abstracts from the records follow. 



Experiment V. August 28, 1916. On skin graft network has separated into 

 large greenish spots, which are entirely different from the light sepia spots just 

 developing on host's skin; in this way it is very easy to identify them as Punc- 

 tatum spots. 



September 2. Host on land-condition. 



September 5. On skin graft 3 yellow spots of the Punctatum type have formed 

 definitely. 



September 22. The spots on skin graft are now bright yellow. 



September 25. Only 1 yellow spot of skin-graft left, which is now still brighter 

 than before. 



October 3. The grafted punctatum eye, which has not been examined until 

 now, shows its ring broken up into yellow and black dots. 



December 7. The 1 yellow spot on skin-graft has become very faint. 



Experiment III. September 7. Yellowish spots and dots of indefinite number 

 and appearance are developing on skin-graft. 



September 22. Two grayish and 1 greenish yellow spot have assumed full 

 distinctness and a small patch of yellowish pigment dots has formed. 



September 22. Host on land-condition. 



September 24. All spots of graft have become greenish yellow, they are dis- 

 tinctly to be recognized as punctatum spots and are absolutely different from the 

 grayish sepia spots of the host. 



September 29. The patch of yellow dots on the graft has developed into a 

 .<iny;le spot of the punctatum type and is extremely bright yellow. 



October 4. Only 2 of the yellow spots on the rear end of the graft are still 

 present. 



October 26. One of these 2 spots has entirely disappeared, the other has been 

 replaced by the chromatophores of the host and has turned sepia. 



November 23. All spots of the graft have gone. 



Experiment VI. Skin-graft started soon after the operation to be replaced by 

 host's skin. 



September 20. In the grafted punctatum eye the outer section of the yellow 

 ring shows dark places. 



September 23. Host on land-condition. 



