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A DISTINGUISHED Essayist has eloquently and truthfully remarked, that "everything in nature is engaged in writing its own history: the planet and the pebble are attended by their shadows, the rolling rock leaves its furrows on the mountain side, the river its channel in the soil, the animal its bones in the stratum, the fern and the leaf inscribe their modest epitaphs on the coal, the falling drop sculptures its story on the sand and on the stone,-not a footstep on the snow or on the ground, but traces in characters more or less enduring the record of its progress.' On the correct interpretation of these autobiographies, inscribed on the rocks and strata by the countless myriads of beings which have successively inhabited the earth, through periods of incalculable antiquity and duration, and whose races are now extinct, is based that most interesting department of natural history which has recently acquired the rank of a distinct branch of modern science, under the title of PALEONTOLOGY.2

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As the remains of animals and plants imbedded in the earth are found in different states of preservation, and more or less

1 Emerson's Essays. Bohn's Edition.

2 From three Greek words, signifying a discourse on ancient beings.


altered in appearance and composition by mineralization, the epithets figured stones, petrifactions, fossils, organic remains, &c., are commonly employed to denote the various conditions in which such relics occur. To avoid confusion it is, therefore, necessary to define the sense in which these terms are used in the following pages; especially as the words "petrifactions," and "fossils," are very generally regarded as synonymous, even by well-educated persons.

And here we must premise that the state of preservation of an organic body, and the chemical changes which it may have undergone in the mineral kingdom, have no necessary relation to its antiquity; for in comparatively modern deposits fossil remains of animals and plants often have acquired a stony hardness, while in rocks of the most ancient epochs they are sometimes as little changed as if they had been entombed in the strata but a few centuries.

1. Fossils, may be defined as the durable parts of animal and vegetable structures imbedded in rocks and strata by natural causes at a remote period; thus wood in the state of lignite, bog-wood, and coal, or of siliceous or calcareous stone, is fossil wood; and bones or shells, whether in an earthy and decaying state, or permeated by calc-spar, flint, or iron, and converted into a hard mineral substance, are alike fossil bones or shells.


2. Petrifactions, are the remains of animals and vegetables in which the original structure is converted into stone, or, in other words, is petrified; such are the silicified stems of trees from Antigua and Germany, and the bones and shells in the Oolitic and Wealden limestones. Such petrifactions may be correctly termed fossil plants, bones, or shells; but similar organic remains, though of equal antiquity, which have not undergone such changes, are not petrifactions in the proper meaning of that term.

3. Incrustations, are neither fossils nor petrifactions, but simply durable parts of animals or vegetables invested with

1 The process by which petrifaction is effected is still involved in obscurity; mineral solutions have permeated the original tissues, and the organic molecules have been replaced by mineral molecules, but how this transmutation is produced is not understood. Mr. Dana's observations and Mr. Jeffery's experiments have, however, elucidated the process of silicification.

travertine or calcareous deposit, which is often compact and of crystalline hardness, but does not permeate the structure of the enclosed substances; such are the so-called petrified eggs, skulls, nests, branches, &c., formed by immersion in the incrusting springs of Derbyshire and other localities.'

These preliminary remarks will suffice for our present purpose, and prepare the observer to find many of the fossil shells, corals, bones, &c. in the collection, presenting but little difference in appearance from similar objects collected on the seashore, or from the beds of streams and rivers; while others will be seen to resemble masses of rock, having only the forms of organic bodies. Certain peculiar conditions in which animal and vegetable remains occur will be explained in the course of our investigations, as well as those indications of former beings observable on the surfaces of rocks and slabs of stone, though all vestiges of the original structures have perished.

And here it will be necessary to remind the reader that the objects we are about to examine possess a twofold interest; for they are to be regarded not merely as relics of extraordinary types of animals and vegetables which flourished in the earlier ages of our globe, and have long since become extinct, but also as natural records of the condition of the earth and its inhabitants, affording indications of the extent and duration of the lands and seas, and of climatorial temperature, &c., through vast periods of time, in ages long antecedent to the creation of the existing species and genera, and the establishment of the present order of animated nature.

In contemplating the principal objects that will come under our examination, it will, therefore, be requisite occasionally to refer to the geological characters of the strata in which they were imbedded, and describe the particular locality whence certain fossils were obtained; these digressions will, I trust, increase the interest of our survey, and prove alike attractive and instructive.

The reader who is wholly unacquainted with the principles of Geology should refer to some elementary work on the science, if he would fully comprehend and enjoy the marvellous histories of the past which will be placed before him in the

1 See "Medals of Creation ;" or, "Wonders of Geology," vol. i. p. 75. (6th edit.) for details. Impressions of leaves on travertine are figured in Pict. Atlas, pl. iii. fig, 2.

course of this investigation. As, however, the arrangement adopted in the Gallery is botanical and zoological, not geological, the uninitiated visitor will have no difficulty in understanding the general descriptions of the most important specimens submitted to his notice.

To remind the observer of the relative age and position of the deposits, and the meaning of certain geological terms which we shall sometimes have occasion to employ in the following narrative, a brief table of the British strata' is subjoined.







PLIOCENE; the upper and newest Tertiary. (Norwich Crag.)

MIOCENE; or middle Tertiary. (Suffolk Crag.)

EOCENE: the lowermost or most ancient Tertiary. (London, Hants, and Isle of Wight. Paris basin.)




Upper Chalk with flints. (South and north Downs of Sussex,
Kent and Surrey; Downs of Hants,
Wilts, &c.

Lower Chalk.

Chalk marl and firestone; or Upper Green Sand. (Godstone,
Undercliff of Isle of Wight.)

Galt or blue chalk-marl. (Folkstone.)

Green sand.

(Shanklin Sands, (Kentish-Rag. Kent. Isle of Wight.)

(Atherfield or Neocomian beds. (Isle of Wight.)

Weald clay, and Sussex and) Wealds of Sussex and Kent, and
Petworth marbles.
the South coast of the Isle of

Hastings sands and clays.
Purbeck strata. (Isle of Purbeck.)

1 Strata are sedimentary deposits that have been formed in the beds of lakes, rivers, and seas, and have subsequently been displaced and elevated above the water by physical causes. A series, or group of strata, is termed a formation; and the fossil remains found in one series or formation differ more or less completely from those of another.

2 Called also the Quaternary or Diluvian period: these deposits cannot be definitively separated from those of the Modern or Human epoch. The gravel beds near Geneva, which closely resemble the newest tertiary drift in materials and position, abound in bones of animals, almost all of which belong to existing species. See M. Pictet's "Palæontologie.”

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