THE OOLITIC SYSTEM. 



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Cidaris coronata. 



Spatangus. 



have been discovered in one instance, by the Marquis of Northampton, in the oolite 

 near Chippenham which have contributed to unfold the organisation of these interesting 

 animals. 



Among radiated animals, or those whose parts are arranged around a common centre, 

 several species of asterias, or star-fishes, a family which began its existence with the 

 oldest silurian deposits, appear in the lias. Examples from the strata in Germany 

 have been found, and very perfect specimens occur in our own country, through the dif 

 ferent members of the oolitic system, and in the chalk formation. Echinites, or sea-urchins, 

 belonging to the same division of animated nature, which make their appearance in the 

 carboniferous system, begin to be largely developed with the dawn of the oolitic, prevailing 

 through the chalk, and presenting a great number of species, now extinct. The echinus 

 of the existing seas is an animal of a globular form, covered with a kind of shell or crust, 



generally thin, beset with rows of 

 spines, and marked with rows of 

 pores, disposed in avenues. It seems 

 a star-fish with the rays coalesced and 

 united together into a spherical case. 

 It has a flat base, often somewhat 

 concave, in which the mouth is always 

 situated. The figure represents a fos 

 sil species, cidaris coronata, or turban 

 echinus, found in France and England, 

 exhibiting the base and profile, with 

 two varieties of the same genus from the Yorkshire oolite, and a specimen of another class, 

 spatangus cor-anguinwn, snake-heart echinus, from the Pyrenees. 



The organic remains of the lias include Crustacea, zoophyta, fishes, marine and terrestrial 

 plants, but it peculiarly commands attention, on account of the abundant relics of 

 saurians, of immense size, which appear to have swarmed in the seas of the liassic period. 

 Sir Everard Home was the first who called public notice to the skeletons of these animals, 

 publishing an account in the year 1814 of some bones found on the coast, between 

 Lyme and Charmouth, in a rock thirty or forty feet above the level of the sea. But 

 the remains examined were incomplete, and the nature and habitat of the animal to 

 which they belonged baffled all inquiry, until the discovery of more perfect skeletons, and 

 the application to them of the great genius of Cuvier, Mr. Conybeare, De la Beche, and 

 others, unfolded a race of water saurians, which received the name of Ichthyosaurus, or 

 fish-lizard, from Mr. Konig, of the British Museum. This strange creature, ranging from 

 five to more than thirty feet in length, of which ten species are enumerated, had the 

 snout of a porpoise, the head of a lizard, the teeth of a crocodile, the vertebrae of a fish, 

 the sternum of an ornithorhyncus, and the paddles of a whale, thus uniting in itself a 

 combination of mechanical contrivances which are now found distributed among three 

 distinct classes of the animal kingdom. "Persons," says Dr. Buckland, "to whom this 

 subject may now be presented for the first time, will receive with much surprise, perhaps 

 almost with incredulity, such statements as are here advanced. It must be admitted that 

 they at first seem much more like the dreams of fiction and romance, than the sober results 

 of calm and deliberate investigation ; but to those who will examine the evidence of facts 

 upon which our conclusions rest, there can remain no more reasonable doubt of the former 

 existence of these strange and curious creatures, in the times and places we assign to 

 them, than is felt by the antiquary, who, finding the catacombs of Egypt stored with the 

 mummies of men, and apes, and crocodiles, concludes them to be the remains of mam 

 malia and reptiles, that have formed part of an ancient population on the banks of the 



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