(_a_) _In water_, either (1) _very_ advanced, large-headed larvae 45
mm. long (instead of 25-30 mm.) with gills already reduced, which had
awkward, embryo-like movements, and in some few days metamorphosed
into small perfect salamanders; or (2) moderately advanced, properly
proportioned larvae, 40-41 mm. long, provided with large gills of (at
first) intrauterine character, which were reduced during aquatic life.
(_b_) _On land_, small (26 mm. long) larvae with rudimentary gills,
having the body rounded instead of being flattened from above downwards,
and an elongated narrow head, which were unable to live in deep water.
These larvae changed to the salamander colour in 10-12 days, and after
four weeks metamorphosed into salamanders 29 mm. long.
(_c_) In the foregoing cases the experimental conditions were not
continued, or in other words, basins of water were provided in which
they could spawn. But if the experimental conditions are continued,
these _Salamandra maculosa_ which were born newt-like (viz., not in a
larval condition), are themselves newt-bearing from the first time they
give birth, using the dry land, and bringing forth only two young, the
normal number for the births of _S. atra_. These young are 40-41 mm.
long, and are dark-coloured, resembling greatly the normal new-born _S.
atra_.
This epitome of the observations illustrating the inheritance of
acquired characters has been very widely quoted, and may not unnaturally
be taken to summarize a wide experience of the modified animals.
Reference to the details given in the same paper shows that, as alleged,
each of the four types of behaviour enumerated was witnessed _once_ only
in the case of each of four females, no two agreeing with each other.
As to the number of the males or their habits nothing is said. The first
female, _a_ (1), bore five young; the second, _a_ (2), bore two, of
which one was a partial albino; the third, _b_, produced four young; and
the fourth, _c_, two as already stated.
In the case of _c_ the details show that the female gave birth
immediately after being transferred from the open-air terrarium to
one indoors, which contained no basin of water. This is the example
of the consequences which follow on a continuance of the experimental
conditions.[17]
Public-domain text, read in full here on John Shaqi.
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