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Updated: May 24, 2025
I need give only one instance, namely, the manner in which the fossils of the Devonian system, when this system was first discovered, were at once recognised by palaeontologists as intermediate in character between those of the overlying carboniferous, and underlying Silurian system.
Geologically speaking, the Carboniferous formation occurs near the close of that group of systems which have been classed as "palaeozoic," younger in point of age than the well known Devonian and Old Red Sandstone strata, but older by far than the Oolites, the Wealden, or the Cretaceous strata.
Dan Pengelly, the sailor with the Cornish patronymic and Devonian birthplace, found an excellent boon companion in the little sallow-faced fellow who had overtaken him a few miles south of Gloucester. And he found the "New Inn," boastful of having given a night's lodging to the Queen and the Earl of Leicester, an expensive but comfortable tavern.
I gasped for the fish had been a ganoid that ancient, armoured form that was perhaps the most intelligent of all life on our planet during the Devonian era, but which for age upon age had vanished, save for its fossils held in the embrace of the stone that once was their soft bottom beds; and the half-globes were Medusae, jelly-fish but of a size, luminosity, and colour unheard of.
At p. 460 of his Manual of Elementary Geology, Sir Charles Lyell gives a list in illustration of this. It appears that in 1709, fishes were not known lower than the Permian system. In 1793 they were found in the subjacent Carboniferous system; in 1828 in the Devonian; in 1840 in the Upper Silurian.
To this Upper Devonian belong a series of limestones and slates well developed at Petherwyn, in Cornwall, where they have yielded 75 species of fossils. Heliolites porosa, Goldf. sp. Portion of the same magnified. Favosites cervicornis, Blainv. S. Devon, from a polished specimen. a. Cyathophyllum caespitosum, Goldf.; Plymouth and Ilfracombe. b. A terminal star. c.
If there were any harmony between the Miltonic account and the circumstantial evidence, we ought to have abundant evidence of the existence of birds in the Carboniferous, the Devonian, and the Silurian rocks. I need hardly say that this is not the case, and that not a trace of birds makes its appearance until the far later period which I have mentioned.
The genus is still better known as a Silurian form, but the spinose species appear to belong exclusively to the "Lower Devonian," and are found in Britain, Europe, and the Cape of Good Hope.
During the progress of Geology, it has over and over again happened that a particular fossil, long considered characteristic of a particular formation, has been afterwards discovered in other formations. Until some twelve years ago, Goniatites had not been found lower than the Devonian rocks; but now, in Bohemia, they have been found in rocks classed as Silurian.
Cassian beds exhibiting an abundant fauna of mixed mesozoic and palaeozoic types, in rocks of an epoch once supposed to be eminently poor in life; witness, lastly, the incessant disputes as to whether a given stratum shall be reckoned devonian or carboniferous, silurian or devonian, cambrian or silurian.
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