I98i Royal Institution. 



forests in which these creatures live. Then, to prevent mischievous 

 eiFects from the decomposition of vegetable matter in countries where 

 it is so luxuriant, decaying plants furnish food to Termites and other 

 insects, which, in their turn, support a peculiar genus of quadrupeds, 

 the Myrmecophaga (or ant-eaters). In closing this part of his sub- 

 ject, the Professor noticed the armour-like, osseous skin of the arma- 

 dillos, which live at the foot of trees, and are, therefore, extremely 

 liable to blows from falling boughs, &c. 



In other parts of the world, where vegetation is abundant, the 

 quadrupeds related with it are generically distinct from those of 

 South America. This adaptation of species to locality having im- 

 pressed itself strongly on his mind in regard to the present globe, the 

 Professor stated, that he early applied himself to inquire whether — 

 4. The extinct species of mammals were localized like the present races. 

 — For this purpose he formed a full and correct catalogue of the fos- 

 sil remains of mammals in our island. He then gave a rapid sketch 

 of the successive races of the extinct mammals, as they have been 

 traced by the fossils in the ascending series of strata in England and 

 Scotland. The first examples of this class are found in the lime- 

 stone slate of Stonesfield, at the base of the middle oolite. These 

 fossils were remains of small insectivorous, and probably marsupial, 

 quadrupeds, associated with remains of beetles, vegetable fossils, 

 shells, and fishes allied to the Cestracion. These recall many of the 

 characteristic features of actual organic life in Australia. During 

 the long period which followed the formation of the Stonesfield slate, 

 and which has permitted the subsequent, successive, and gradual accu- 

 mulation of enormous masses of sedimentary rocks, viz. great oolite, 

 cornbrash, forest marble, Oxford clay, calcareous grit, coral rags, 

 Kimmeridge clay, Portland stone, Wealden, gault, greensand, chalk, 

 no trace of a mammalian fossil has been found. In England we first 

 obtain evidence of that class of animals in the debris of some conti- 

 nent, poured out by vast rivers upon the surface of the chalk, form- 

 ing masses 1000 feet in depth — the Plastic and London clays. Here 

 are remains of great Tapiroids, as Lophiodon and Coryphodon, and 

 smaller pachyderms, like peccaries — Hyracotherium. Here, with 

 boa constrictors, are turtles, sharks, fossil palms, and other forms of 

 tropical vegetation. At the same period there were alternating fresh- 

 water and marine deposits in continental Europe, filling up a vast 

 excavation of chalk, called the Paris basin, and forming the founda- 

 tions on which that city is built, analogous to the clays on which 

 London stands. Here Cuvier first discovered and described the Ano- 

 plotherium, Palaotherium and Chceropotamus . 



The Professor then briefly noticed the existence of similar calca- 

 reous freshwater and marine deposits in the Isle of Wight, and ad- 

 verted to the discoveries of Mr. Allen and Mr. Pratt. It was, how- 

 ever, remarked, that little is gained by comparison of eocene and 

 existing mammals, excepting so far as these indicate a great change 

 in the distribution of earth and sea, and an accompanying alteration 

 of climate. With the last layer of eocene deposits, we lose in En- 

 gland every trace of the peculiar mammals of that period. A vast 

 series of geological operations took place, from which the miocenc 



