The Transformation of the Mexican AxoiotL 559 



transformation into Amblystoma. For brevity I 

 shall designate this as No. I., and the succeeding 

 specimens by corresponding Roman numerals. 



" In order to bring about this metamorphosis, 

 on December ist, 1874, No. I. was placed in a 

 large-sized glass vessel containing earth arranged 

 in such a manner that, when the vessel was filled 

 with water, only one portion of the surface of the 

 earth was entirely covered by the liquid, and the 

 creature in the course of its frequent perigrinations 

 was thus more or less exposed to the air. The 

 water was gradually diminished on the following 

 days, during which period the first changes made 

 their appearance in the Amphibian the gills 

 commenced to shrivel up, and at the same time 

 the creature showed a tendency to seek the 

 shallowest spots. On December 4th, it took 

 entirely to the land, and concealed itself among 

 some damp moss which I had placed on a heap 

 of sand on the highest portion of the earth in the 

 glass vessel. At this period the first ecdysis 

 occurred. Within the four days from the ist to 

 the 4th of December, a striking change took 

 place in the external appearance of No. I., the gill- 

 tufts shrivelled up almost entirely, the dorsal 

 crest completely disappeared, and the tail, which 

 had hitherto been broad, became rounded and 

 similarly formed to that of a land salamander. 

 The grey-brown colour of the body changed gra- 

 dually into a blackish hue ; isolated spots, at first 



