CORRESPONDENCE. 87 



shells, the Venus, Cytherea, Helices, and Cardium, and the 

 remains of existing animals : it is termed the new Pliocene 

 formation or period. Although new in comparison with the others, 

 it is yet of high antiquity in regard to man. The next structure is 

 a hed of plastic clay, varying from one foot to forty feet in thickness. 

 This lies upon another bed of sand, containing the remains of ani- 

 mals, some of which are extinct. These strata clearly demonstrate 

 a deposit after each action of the tide. There is a process going 

 on, or was in operation fourteen years ago, on the levels connected 

 with the river Trent, in Lincolnshire, termed warping : it was ac- 

 complished by means of two sluices which conveyed the tide to the 

 upper part of the level. Flood-gates being closed until low water, 

 gave time for a deposit ; upon raising up these gates clear water 

 passed off, leaving a coat of earth on the surface of the land. The 

 owners of the property continued this operation from three to six 

 years, according to effects, rendering land which was nearly value- 

 less worth from £55. to £75. per acre, consequently capable of the 

 higher culture. This example tends to illustrate the regular depo- 

 sits which are observable in all the aqueous formations. I have not 

 only found in this hed portions of the Mammoth or extinct Ele- 

 phant, the Asiatic Elephant, Rhinoceros, Lion or Tiger, Hyena, 

 Horse, Buffalo or Ox, Elk, Deer, and Boar or Sus scrqfa, but nu- 

 merous shells, viz., Uiiio, Helix, Melania, Cytherea, Cardium, In- 

 fundibulum, Echinulatum, Micula, Oliva, Venus, &c. This is 

 termed the old Pliocene formation. Dr. Buckland, in remarking 

 on this period in the tiridgervater Treatise, vol. i., p. 95, says : — 

 " It appears that at this epoch the whole surface of Europe was 

 densely peopled by various orders of mammalia ; that the numbers 

 of the Herbivora were maintained in due proportion by the con- 

 trolling influence of the Carnivora, and that the individuals of 

 every species were constructed in a manner fitting each to its own 

 enjoyment of the pleasures of existence, and placing it in due and 

 useful relations to the animal and vegetable kingdoms by which it 

 was surrounded. Every comparative anatomist is familiar with the 

 beautiful examples, mechanical contrivance, and compensations 

 which adapt each existing species of Herbivora and Carnivora to 

 their own peculiar place and state of life. Such contrivances began 

 not with living species. The geologist demonstrates their prior 

 existence in the extinct forms of the same genera which he disco- 

 vers beneath the surface of the earth, and he claims for the author 

 of these fossil forms, under which the first types of such mechanism 

 were embodied, the same high attributes of wisdom and goodness, 



