IN THE TERTIARY FORMATIONS. 285 
belong to extinct genera, and not one is identical 
with any existing species ; they are all marine, 
^nd the greater number approach most nearly 
to forms now living within the tropics.* 
To this first period of the Tertiary formations 
belong also the Fishes of the London clay ; 
many of the species found in Sheppy, though 
t>ot identical with those of Monte Bolca, are 
closely allied to them. The Fishes of Libanus 
also are of this era. The Fishes in the gypsum 
af Mont Martre are referred to the same period 
by M. Agassiz, who differs from Cuvier, in at- 
tributing them all to extinct genera. 
The Fishes of Oeningen have, by all writers, 
been referred to a very recent local lacustrine 
•icposit. M. Agassiz assigns them to the second 
period of the Tertiary formations, coeval w’ith 
the Molasse of Switzerland and the sandstone 
af Fontainbleau. Of seventeen extinct species, 
ane only is of an extra-European genus, and all 
belong to existing genera. 
The gypsum of Aix contains some species 
referrible to one of the extinct genera of Mont 
dartre, but the greatest part are of existing 
§anera. M. Agassiz considers the age of thisfor- 
M. Agassiz has re-arranged these fishes under 127 Species, 
^ extinct, and 77 Genera. Of these Genera 38 are extinct, and 
still living; the latter present 81 fossil species at Monte Bolca, 
^nd the former 46 species. These 39 living Genera appear for 
® first time in this formation. 
