HABITS OF THE AXOLOTL. 481 
several adults from the larva, and I have been told that sire- 
dons in the mountains among the miners’ camps near Salt 
Lake City leave the water and transform. It thus appears 
that in the elevated plateaus* as well as at the sea-coast, some 
siredons transform while others do not. Mexican siredons 
have for a number of years been bred from eggs in the 
aquaria of Kurope, laying eggs the second year. 
The change from the larva to the adult consists, as we have 
observed, in the absorption of the gills, which disappear in 
about four days ; meanwhile the tail-fins begin to be absorbed, 
the costal grooves become marked, the head grows smaller, 
the eyes larger, more protuberant, and the third day after 
the gills begin to be absorbed the creature becomes dark, 
spotted, and very active and restless, leaving the water. Their 
metamorphosis may be greatly retarded and possibly wholly 
checked by keeping them in deep water. The internal 
changes in the bones of the head and in the teeth are very 
marked, according to Dumeril. 
Experiments made in Europe show that the legs and tail 
of the axolotl, as of other larval salamanders, may be repro- 
duced. We cut off a leg of an axolotl the first of November ; 
it was fully reproduced, though of smaller size than the 
others, a month later. The tail, according to Mr. L. A. 
Lee, if partly removed, will grow out again as perfect as ever, 
vertebree and all. 
The Tritons or water-newts, represented by our common, 
pretty spotted newt, Diemyctylus viridescens Rafinesque, are 
also known in Europe to become sexually mature in the larval 
state when the gills are still present, as has been observed by 
three different naturalists. The female larva of Lissotriton 
punctatus has been known to lay eggs. 
Order 4. Gymnophiona.—The blind snake with its several 
allies is the representative of this small but interesting order. 
* It has been stated by De Saussure, Cope, Marsh, and more recently 
by Weismann, that the siredon does not change in its native elevated 
home. No naturalist has seen the Mexican siredon transform into an 
Amblystoma, but as it does so in abundance in Wyoming and Utah, 
it probably transforms in Mexico. (The adult Mexican form has receni- 
ly been found, and is at the Smithsonian Institution.) 
