DISAPPEARANCE OF LIMBS 
facts are not without interest. Why this black and 
slimy newt should be called Siven is not clear. They do 
not chirp or sing, and indeed are voiceless, like other 
newts. They are not enchantresses and do not play on 
cords. On the contrary, they are black and evil-looking, 
not alluring except indeed to the naturalists, to whom 
they present many points of interest. This animal 
grows to about two feet in length, and lives exclusively 
or at least very nearly entirely, in muddy ditches, where 
it finds its animal prey. The accurate John Hunter 
was the first to detect the real nature of the siren, and 
placed it between amphibians and fishes. A retrograde 
step was taken by Camper the Dutchman, who called it 
a murena, or eel, an error which is perpetuated to-day 
by its vernacular name of ‘“ Mud-eel,’ The siren has 
external fringed gills like the axolotl. But there is no 
reason to suppose that it is, like the axolotl, a larval 
form ready to blossom out into a more fully formed and 
gill-less newt when forced to leave its streams. For in 
the first place its degradation is shown by the missing 
hind limbs, and in the second place it has a set of larval 
gills which give place to the therefore permanent gills 
of the adult. It has had its chance as a larva, and has 
failed to take advantage of it. As with other aquatic 
creatures, it is the hind limbs which have gone. Thus 
the whales have not a trace of these: and in the seal 
and sea-lions they are more or less bound up with the 
tail, and clearly on the wane. In terrestrial animals 
which have undergone degeneration, it is rather the 
fore limbs that go first, as witness the snakes and many 
tail-less lizards. 
THE AXOLOTL 
There is nothing more interesting at the Zoo than the 
swarthy American newts, called axolotls, unless it be 
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