PL 1, Fig. 49), a large Ranatra, and several
Coleoptera.
Numerous fossil Insects have recently been discovered
in the Tertiary Gypsum of Fresh-water
formation at Aix, in Provence. M. Marcel de
Serres speaks of sixty-two Genera, chiefly of the
Orders Diptera, Hemiptera, and Coleoptera ;
and Mr. Curtis refers all the specimens he has
seen from Aix to European forms, and most of
them to existing Genera.* Insects occur also
in the tertiary Brown coal of Orsberg on the
Rhine.
General Conclusions.
We have seen from the examples cited in the last
four sections, that all of the four existing great
Classes of the grand Division of Articulated
animals, viz. Annelidans, Crustaceans, Arach-
nidans, and Insects, and many of their Orders,
had entered on their respective functions in the
natural world, at the early Epoch of the Transition
Formations. We find evidences of change
in the Families of these Orders, at several periods
of the Secondary and Tertiary series, very distant
from one another; and we further find each
Family variously represented during different
intervals by Genera, some of which are known
* See Edinburgh New Phil. Journ. Oct. 1829.
only in a fossil state, whilst others (and these
chiefly in the lower Classes,) have extended
through all geological Eras unto the present
time.
On these facts we may found conclusions
which are of great importance in the investigation
of the physical history of the Earth. If
the existing Classes, Orders, and Families of
marine and terrestrial Articulated animals have
thus pervaded various geological epochs, since
life began upon our planet, we may infer that
the state of the Land and Waters, and also of the
Atmosphere, during all these Epochs, was not so
widely different from their actual condition as
many geologists have supposed. We also learn
that throughout all these epochs and stages of
change, the correlative Functions of the successive
Representatives of the animal and vegetable
kingdoms have ever been the same as at
the present moment; and thus we connect the
entire series of past and present forms of organized
beings, as parts of one stupendously grand,
and consistent, and harmonious Whole.