Axolotl

Axolotl (the Aztec word), an amphibian form occurring abundantly in some Mexican lakes, and found widely distributed in the Western United States. It used to be ranked among the forms which permanently retain their gills (Perennibranchiata), but more complete observation has shown that it develops into a gill-less adult form (Amblystoma) like a salamander. Both forms saline character of the shore of some of the lakes apparently prevents the gilled axolotls in these cases from leaving the water and becoming lung-breathing adults, while in other instances drying up has doubtless acted as a condition forcing them to the adult mode of respiration. Thus the axolotl of Lake Como on the summit of the Rocky Mountains is said to be always transformed into Amblystoma, while in other cases the larval form seems to persist if the external conditions be favourable for breathing by gills. The axolotl is plump and short-legged, from 8 to 10 inches in length, of a dark colour with spots, and with the common amphibian character of slightly changing its colour (see CHROMATOPHORES). It bears three feathery gills on each side of its neck. Though in one sense larval, it is nevertheless sexually mature. It is esteemed a delicacy in Mexico. See AMBLYSTOMA.