Dale,* and also of the wing of a Corydalis, which will be noticed in our description of Pl. 46′′.

It is very interesting and important, to have discovered in the Coal formation fossil remains, which establish the existence of the great Insectivorous Class Arachnidans, at this early period. It is no less important to have found also in the same formation the remains of Insects, which may have formed their prey. Had neither of these discoveries been made, the abundance of Land plants would have implied the probable abundance of Insects, and this probability would have involved also that of the contemporaneous existence of Arachnidans, to control their undue increase. All these probabilities are now reduced to certainty, and we are thus enabled to fill up what has hitherto appeared a blank in the history of animal life, from those very distant times when the Carboniferous strata were deposited.

The Estuary, or Fresh-water formation of those strata of the Carboniferous series which contain shells of Unio, in Coalbrook Dale, and in other Coal basins, renders the presence of Insects and Arachnidans in such strata, easy of explanation; they may have been drifted from adjacent lands, by the same torrents that transported the ter

* Our figures (Pl. 46". Figs. 1. 2.) represent these fossils of their natural size. See description of this Plate for further details respecting them.

INSECTS IN SECONDARY AND TERTIARY STRATA. 411

restrial vegetables which have produced the beds of Coal.

The existence of the wing-covers of Insects in the Secondary Series, in the Oolitic slate of Stonesfield, has been long known; these are all Coleopterous, and in the opinion of Mr. Curtis. many of them approach most nearly to the Buprestis, a genus now most abundant in warm latitudes. (See Pl. 46". Figs. 4. 5. 6. 7. 8. 9. 10.)*

Count Munster has in his collection twentyfive species of fossil Insects, found in the Jurassic Limestone of Solenhofen; among these are five species of the existing Family of Libellula, (See

* M. Aug. Odier has ascertained, that the Elytra and other parts of the horny covering of insects, contain the peculiar substance Chitine, or Elytrine, which approaches nearly to the vegetable principle Lignine; these parts of Insects burn without fusion, or swelling, like horn, and without the smell of animal matter; they also leave a Coal which retains their form.

M. Odier found that even the hairs of a Scarabæus nasicornis retained their form after burning, and therefore concludes that they are different from the hairs of vertebral animals. This circumstance explains the preservation of the hairs on the horny cover of the Bohemian Scorpion.

He ascertained also that the Sinews (Nervures) of Scarabæi, are composed of Chitine, and that the soft flexible lamina of the shell of a crab, which remain after the separation of the Lime, also contain Chitine.

Cuvier observes, that the Integuments of Entomostracans, are rather horny than calcareous, and that in this respect they approximate to the nature of Insects and Arachnidans. See Zoological Journal. London, 1825, vol. i. p. 101.

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, Arachnidans, 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.

CHAPTER XVII.

Proofs of Design in the Structure of Fossil
Radiated Animals, or Zoophytes.

THE same difficulties which we have felt in selecting from other grand Divisions of the animal kingdom, subjects of comparison between the extinct and living forms of their respective Classes, Orders, and Families, embarrass our choice also from the last Division that remains for consideration. Volumes might be filled with descriptions of fossil species of those beautiful genera of Radiated Animals, whose living representatives crowd the waters of our present seas.

The result of all comparisons between the living and fossil species of these families would be, that the latter differ almost always in species, and often in genus, from those which actually exist; but that all are so similarly constructed on one and the same general Type, and show such perfect Unity of Design throughout the infinitely varied modifications, under which they now perform, and ever have performed the functions allotted to them, that we can find no explanation of such otherwise mysterious Uniformity, than by referring it to the agency of one and the same Creative Intelligence.