150 



mations, that the insects of this age are, with a few exceptions, 

 closely allied to forms now in existence, a result, upon the whole, 

 as Mr. Brodie observes, " quite the reverse of that which we are 

 led to infer from the rest of the fossils of the Secondary Eocks. 

 Thus while we have in the Purbecks many strange and extinct 

 races among other divisions of the animal kingdom, the insects 

 which accompany them are more nearly related to existing genera, 

 and present, upon the whole, a decidedly European character ; 

 indeed, the greater part must have been of the inhabitants of a 

 temperate climate, although some few were adapted to a much 

 higher temperature. This is the more remarkable because the 

 colossal saurians, palms, and tree ferns in these strata, 

 evidently belonged to a hot country. It is true that these 

 are chiefly confined to the upper division ofthis deposit " 

 (i.e., the Wealden proper) ; "but many of the fossils in the 

 lower or Purbeck beds are equally conclusive in the matter, 

 as the remains of the Megalosaurus, crocodiles, turtles, and 

 cycas clearly prove." 



KiMjiERiDGE Clay. 



Below the well known Portland stone, so extensively 

 quarried for building purjDoses, is a dense bed of sand called the 

 Portland sand, immediately below which is the Kimmeridge clay. 

 The Kimmeridge clay is said by Lyell to consist, in great part, of 

 a bituminous shale, sometimes forming an impure coal several 

 hundred feet in thickness. At Eingstead, in Dorsetshire, 

 according to Mr. Brodie, this clay is traversed by a bed of sandy 

 laminated stone about two feet thick, and this is succeeded by 

 thick strata of dark coloured shale and clay, containing large 

 blocks of Septaria, in one of which Mr. Brodie discovered a 

 striated elyti'on of a small beetle. "With this exception, I find no 

 record of the discovery of any insect remains from this part of 

 the Upper Oolite system. 



Middle Oolite. 

 Oxford Clay. 



The Oxford clay consists principally of laminated beds of 



