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spring in the case of the common newt ; hut because the gilled 
larval form was capable of reproduction, and had therefore 
naturally been considered as an adult. No cause could be assigned 
for this strange and sudden assumption of a higher mode of life ; 
for the converted axolotls had been exposed to no different 
conditions to their unconverted fellows. 
Dum4ril tried the experiment of cutting off the gills of an 
ordinary axolotl ; but the animal only produced a new set of gill- 
tufts, and stuck pertinaciously to its old habits. Lately, however, 
a German lady, Fraulein Marie von Chauvin, has overcome 
all difficulties, and triumphantly evoked Amblystoma out of 
more than one axolotl, by gradually accustoming the animal 
to live on land, and by paying throughout the process the greatest 
attention to health and diet ; and believing that a description of 
her labours will be instructive to our members, I will briefly 
recount her plans. At first the five specimens selected were kept 
in a tank not quite covered with water, but they did not thrive ; so 
the supply of water was increased, and on restoration to health, 
they were indulged in shallow water by day, and a deeper bath at 
night. They now throve perfectly well, but showed no disposition 
to metamorphosis, and actually retrogressed in development : they 
were then placed on land as they were, gills and all ; but the change 
was not favourable : they lost appetite, and free cutaneous respira 
tion, so essential to the comfort of an amphibian was impeded by 
particles of earth and moss adhering to their slimy skins. A tepid 
bath twice a day remedied that difficulty ; but then the skin dried 
so rapidly, that the process of casting it became difficult, and 
eventually they were kept moist in wet moss after their bath. 
Three out of the five specimens made up their minds to die rather 
than improve, and after having lived fifty days on land they died 
from obstinately refusing their worm diet : at the time of their 
death, however, the gill-tufts, tail-fins, and other larval character- 
istics had already become much reduced. The behaviour of the 
two remaining specimens was more satisfactory : they showed a 
marked decrease in the size of gill-tufts and tail-fin after they had 
lived a few days on land; before long the atrophy of the gill-tufts 
