14 THE SUNKEN ISLAND OF ATLANTIS. 
^ 
has been committed in tLis instance is more than proved by the fruit, 
which has been met with in a fossil state, and closely resembles 
that of the Amber-tree. The fragments of leaves submitted next, 
one of which has been found in Switzerland, the other in limestone 
beds ia Sinigaglia, are instantly recognized as those of the North Ame- 
rican Tulip-tree (Liriodendron tidipifera, Linn.). Though they may 
not be quite identical with them, they must, at all events, be re- 
garded as derived from the nearest ally. In Iceland, besides the leaves, 
the fniits (of Z. Frocaccinii, Ung.) have been observed. Amongst the 
other fragments frequently. found in lignite are branches covered with 
minute lancet- or nearly needle-shaped leaves, pointing towards a 
Conifer, wliich is not met w^th in Europe, but has an extensive geogra- 
phical range in North America. It belongs to the oldest vegetable 
monuments of that country, and is the Taxodium distichum, Eich. 
Other fossils of the lignite beds point towards trees, of which several 
species at present inhabit North America. They belong to the genus 
Nysm, The fruits and seeds of Pavia and Rohinia, occasionally en- 
countered, prove that these two genera, now confined to North Ame- 
rica, and admitted into our gardens as exotics, at one time flomished 
in Europe. It is well known that Europe is destitute of Walnuts, the 
one cultivated being derived from the woody mountains of the southern 
Caucasus. But a great number of different nuts are very common in 
lignite formations, and if compared with a large North American 
genua their close resemblance at once becomes manifest : the so-called 
grey Hickory {Jiiglans cinerea^ Lmn.) can scarcely be distinguished 
from the fossil Jnglans tepjirodes^ Ung« I might enlarge upon the dif- 
ferent Maples, Oaks, Poplars, Hornbeams, Eirs, and Yews of the 
lignite flora, the nearest allies of which are not the species still exist- 
ing in Europe, but almost exclusively those in North America ; and I 
might add a great number of other details, all proving that the ligidte 
flora had not a European but a North American character. This con- 
clusion, which I published about fifteen [now twenty] years ago, has 
not been shaken by any subsequent investigations ; on the contrary, 
every year has furnished additional proofs of its accuracy, now ena- 
bling me to give the following list of the fossil species and the corre- 
sponding living types of the North American flora. 
