The Transformation of the Mexican Axolotl. 567 



" Siredon Mexicanus vel Humboldtii" * but sub- 

 sequently, in his amplified work 8 on the trans- 

 formation of the Axolotl observed in the Jardin 

 des Plantes, he retracted this view, and after a 

 critical comparison of the five described species 

 of Siredon^ he came to the conclusion that the 

 species in the possession of the Paris Museum was 

 probably Siredon Lichenoides (Baird). All the 

 transformations of Axolotls observed in Europe 

 must consequently be referred to this species, 

 since they were at least as far as I know all 

 derived from the Paris colony. My own experi- 

 mental specimens were also indirectly descended 

 from these. 



Now it must be admitted that this does not 

 coincide with the fact that the Amblystoma form 

 which Dumeril first obtained from his Axolotls 

 agreed with Cope's species, A. Tigrinum, while on 

 the other hand we learn from Marsh 7 that Siredon 

 Lichenoides (Baird), when it does undergo meta- 

 morphosis, becomes transformed into Amblystoma 

 Mavortium (Baird). 



Marsh found Siredon Lichenoides in mountain 

 lakes (7000 feet above the sea) in the south- 



Compt Rend., vol. Ix. p. 765 (1865). 



' Nouvelles Archives du Museum d'Histoire Nat. Paris, 

 1866, vol. ii. p. 268. 



T Proc. Boston Soc, vol. xii. p. 97 ; Silliman's Amer. Journ., 

 vol. xlvi. p. 364 ; reference given in " Troschel's Jahres- 

 bericht " for 1868, p. 37. 



