IN THE TEUTIARY FORMATIONS. 285 
belong to extinct genera, and not one is identical 
with any existing species; they are all marine, 
and 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 
not 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 
of 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 
deposit. M. Agassiz assigns them to the second 
period of the Tertiary formations, coeval with 
the Molasse of Switzerland and the sandstone 
of Fontainbleau. Of seventeen extinct species, 
one 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 
Martre, but the greatest part are of existing 
genera. M. Agassiz considers the age of this for- 
* M. Agassiz has re-arranged these fishes under 127 Species, 
all extinct, and 77 Genera. Of these Genera 38 are extinct, and 
39 still living; the latter present 81 fossil species at Monte Bolca, 
and the former 46 species. These 39 living Genera appear for 
the first time in this formation. 
