CADUCIBRANCHIATA. 55 



Amblystonia Mexicanum, Cope. 



Synonyms, Gyrinus Mexicanus, Shaw and Nodder; 

 Siren pisciformis, Shaw, Daudin, Home and Mayer; 

 Gyrinus edulis, Hernandez; Lusus aquarum, Nierem- 

 berg; Piscis ludricus, Hypochihcn pisciformis, Graven- 

 horst; Axolotes guttatus, R. Owen; Axolotes macula- 

 tus, Gray; Siredon Humboldtii, Dumeril and Bibron. 



Color brown or dark gray ; irregularly black spotted, 

 extending upon their borders in radial lines; tail and 

 belly also, spotted; dorsal membrane and upper cau- 

 dal united, the latter curved ; subcaudal fin smaller and 

 nearly straight. 



Hernandez was certainly the first to discover this an- 

 imal, and his allusion to it was so singular as to have 

 been transcribed by naturalists. As it may be of inter, 

 terest to some it is given here. 



"Illuvies menstrua et Lubricus gestus unde nomen 

 meruit Axolotl id est Lusus aquarum. Genus quoddam 

 est piscium lacustrium, molli cute intectum, ac Lacer- 

 tarum more quodrupes, dodrantis longitudine, pollicem 

 que crassum et si interdum cubitum exedat. Vulvam 

 habet mulieri similliman, ac venter ejus maculis fuscis 

 distinguitur. Corpore medio ad caudam usque, mempe 



