J. P. BLAKE ON THE KIMMERIDGE CLAY OP ENGLAND. 211 



supposing each of these separate exposures to occupy a separate 30 

 feet, which would give 450 feet ; but such estimates are entirely 

 conjectural. 



Comparing now the Lower Kimmeridge of other counties with this 

 typical development in Lincolnshire, I of course include the whole of 

 the " Middle Kimmeridge of Filey Bay " of Mr. Judd in this division. 

 It contains several of the characteristic fossils, with others that have 

 not been met with in Lincolnshire, among which may especially be 

 mentioned Exogyra virgula. A portion of his "Lower Kimmeridge" 

 is also probably of this division. 



I have already stated that I regard the base of the pit at Ely as 

 Lower Kimmeridge, partly on account of its more clayey character, 

 but chiefly from its contained fossils, especially Ammonites serratus, 

 A. longispinus, Area rhomboidalis, Astarte ovata, JSerpula tetra- 

 gona, Avicula cedilignensis, Pecten Grenieri, Dentalium Quenstedti, and 

 Lingula ovalis. Several other fossils are collected at this pit • but as 

 this is the only pit I have seen in Cambridgeshire, they will appear 

 in the general list. 



The great mass of the Kimmeridge Clay of the " inland counties " 

 belongs to this lower division, which accounts for Professor Phillips 

 saying that the upper portion is most fossiliferous — that is, the region 

 of Market Easen. I have not very carefully examined the clay in 

 this range, as its fossils have been already collected and recorded, 

 but only satisfied myself of its general accordance with the Lower 

 Kimmeridge of Lincolnshire at Swindon and at Hartwell. The clay 

 is far more sandy than anywhere in that county, and contains 

 several fossils peculiar to the district. At the former place, after 

 very little if any Upper Kimmeridge, several bands are seen in 

 some large brick-pits now in full operation, and very fossiliferous. 

 In the nearest but one to the railway occurs a strong band of lime- 

 stone full of Amm. bipleos, a feature not seen elsewhere ; and the beds 

 dip more than 20° to the S. The dark clay at the base of the next, 

 in which great septarian doggers occur at the top, has many layers 

 of compressed Thracia depressa, which reminds one of a similar 

 abundance of this shell at Weymouth. Prof. Phillips mentions no 

 fossils from the Kimmeridge Clay of Swindon in his list ; nor can I 

 find any account of them. Those that I found are the following, 

 though there must be many more : — 



Ichthyosaurus, sp. 

 Ammonites biplex, Sow. 

 Cerithium multiplicatum, Bla. 

 Dentalium Quenstedti, Bla. 

 Trigonia muricata, Gold/. 

 — — incurva, Bennett. 

 Astarte supracorallina, D' Orb. 

 Nucula menkii, Bom. 

 Area mosensis, Buv. 

 Lucina substriata, Bom. 

 ? balmensis, Cont. 



Cardium striatulum, Sow. 

 Thracia depressa, Sow. 

 Pholadomya, sp. 

 Perna mytiloides, Lam. 



■ Plambarti, Bollf. 



Modiola pallida, Sow. 



semiplicata, Buv. 



Exogyra virgula, Desk. 



nana, Sow. 



Scalpellum reticulatum, Bla. 



To those recorded from Hartwell I have to add the following 

 very characteristic forms : — 



Q. J. G. S. No. 122. q 



