the deposit, some of them, to the minutest organ, in the highest state of preservation—all of them extinct—and nearly four-fifths belonging to a division Pachydermata or thick-skinned animals. Immediately above the gypseous formation is an oyster-bed, of great superficial extent; this is succeeded by beds of sand, entirely destitute of fossils, forming a suitable covering to the countless millions which lie interred beneath. Reader! pause and reflect upon this enumeration of the rocky strata, and their contents, which compose the Paris basin. What vast accumulations, now of terrestrial floods, now of inroads from the ocean—here a deposit, testifying to the fact of some great inland lake, with huge monsters browsing on its banks or reposing in its shallows—there another, bearing witness to “the strength of a mountain river,” combating with the waves of an estuary, and each wearying of the conflict and mingling their spoils from land and sea in one common mass. Neptune is again triumphant, and leaves as the trophies of victory whole families and tribes of his own domains. Silvanus now asserts and establishes his reign, and the Genet, Raccoon, Opossom, the Squirrel, Woodcock, and Buzzard are there to proclaim his sway. The Nereids too had their doings, and both genera and species of seven extinct nondescript fishes show their powers. And, last of all, come the Naïads of the streams, presenting you with their offering in the Quail, Curlew, and Pelican, along with Tortoises and Crocodilians. Count and enter upon your list, as found in the gypseous formation alone, eleven or twelve species of the Palæotherium, an animal partaking of the respective structures of the rhinoceros, the horse, and the tapir; of the Anoplotherium five species, commingling the light and graceful form of the gazelle with the conformation of the camel; fifteen species of the Lophiodon, closely allied to the former, but partaking also of the qualities of the hippopotamus; seven species of the Anthracotherium, a creature whose dimensions through the various members of the family swell out from the size of the hog to that of the hippopotamus; the Chæropotamus, allied to the suidæ, and forming a link between the Anoplotherium and the existing Peccary; and, lastly, as closing the list of this remarkable race of thick-skinned animals, we are presented with specimens of the Adapis, of hedgehog appearance, but in size three times larger, and uniting in characters the insectivorous carnivora with the Pachydermata.