86 VESTIGES OF THE 



formation, * including what are called Kimmeridge clay 

 and Portland oolite. In Yorkshire there is an additional 

 group above the lias, and in Sutherlandshire there is 

 another group above that again. In the wealds (moor- 

 lands) of Kent and Sussex, there is, in like manner, 

 above the fourth of the Bath series, another additional 

 group, to which the name of the Wealden has been given, 

 from its situation, and which, composed of sandstones 

 and clays, is subdivided into Purbeck beds, Hastings 

 sand, and Weald clay. 



There are no particular appearances of disturbance 

 between the close of the new red sandstone and the 

 beginning of the oolite system, as far as has been 

 observed in England. Yet there is a great change in the 

 materials of the rocks of the two formations, showina* 

 that while the bottoms of the seas of the one period had 

 been chiefly arenaceous, those of the other were chiefly 

 clayey and limy. And there is an equal difference 

 between the two periods in respect of both botany and 

 zoology. While the new red sandstone shows compara- 

 tively scanty traces of organic creation, those in the oolite 

 are extremely abundant, particularly in the department 

 of animals, and more particularly still of sea mollusca, 

 which, it has been observed, are always the more con- 

 spicuous in proportion to the predominance of calcareous 

 rocks. It is also remarkable that the animals of the 

 oolitic system are entirely different in species from those 

 of the preceding age, and that these species cease before 

 the next. In this system we likewise find that uniformity 

 over great space which has been remarked of the Faunas 

 of earlier formations. " In the equivalent deposits in 

 the Himalaya Mountains, at Fernando Po, in the region 

 north of the Cape of Good Hope, and in the Ptun of 

 Cutch, and other parts of Hindostan, fossils have been 



