xTii PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



Ammonites Murchisonce* from the Dogger, A. Humphreysianusf and. 

 A. Parlcinsoni from the Gristhorpe beds. These three species oc- 

 cupy in Gloucestershire three zones in the Inferior Oolite, in the 

 order here mentioned. In the same order they are reported to lie 

 on the Yorkshire coast, — Ammonites Parlcinsoni occupying the higher 

 zone in each case, and A. Murchisonce the lower. This remarkable 

 analogy makes the palseontological evidence in favour of the slightly 

 greater antiquity of these oolitic beds preponderate, and renders a 

 re-examination of the oolite of North Lincolnshire and South York- 

 shire a very desirable work. I do not intend to neglect it. 



§ Beds below the Chalk. 



Nor are we entirely free from perplexity in regard to some other 

 deposits long known and much considered. The great "Wealden 

 series, so interesting for its remains of the land and fresh waters, held 

 its place in the Oolitic group, according to all geological works-, until 

 within a few years. It has now been transferred by several writers 

 to the Cretaceous group. This has been done, however, without the 

 discovery in it of Cretaceous species, without any question of the 

 analogy to the Oolites, — of the flora, which much resembles that of 

 Stonesfield — or the fauna (such as it is), whether invertebrate, as 

 Paludina and Unio, or vertebrate, as Lepidosteus, Megalosaurus, and 

 Cetiosaurus. No doubt Hylaiosaurus and Iguanodon occur also in 

 the Lower Greensand ; but that is hardly a sufficient argument. 



According to the view which seems to me probable, these Wealden 

 beds re-appear near Oxford, and occupy some considerable tracts to 

 the north-east, probably covered by, rather than mixed with, Lower 

 Greensand beds, though not so distinctly as in the typical "Wealden. 

 The Eed Chalk of Yorkshire is perfectly conformed to, and even 

 alternates with, White Chalk, and was classed by me with that de- 

 posit. It has been referred by some later writers to the parallel 

 of the Gault or Lower Greensand ; and Hunstanton Cliff is often 

 quoted in support of this view. But, as I am reminded by Sir C. 

 Lyell, who has lately inspected the Speeton Cliffs, the Red Chalk 

 occurs in a well at Mildenhall, in the White Chalk. I believe we 

 must leave it in the natural alliance formerly assigned to it, or 

 admit two bands of Eed Chalk of unequal antiquity J. In the blue 

 clays at Speeton there occur, as I formerly remarked, Kimmeridge 

 Clay fossils at the bottom, and Gault fossils at the top. In some 

 late visits, I have marked several successive zones of fossils in this 

 clay; I shall probably before long publish in a revised form my 

 ancient section of the Coast, so as to include much additional 

 information as to Speeton, Gristhorpe §, and the northern cliffs. 



* I have observed this species among the fossils of the oolitic Dogger beds 

 (Inferior Oolite) of Thirsk, collected by the Kev. C. Johnstone. 



t This I also found at Gristhorpe, 1855. 



J General Emmett finds the Eed Chalk of Yorkshire to contain a very large 

 proportion of calcareous matter, and to be in some specimens fidl of Foramini- 

 fera. My specimens from Hunstanton are very full of Rotalice. 



§ In the section of Gristhorpe Cliff printed in Geol. Journ. vol. xiv. p. 89, 



