9 



NOTE ON THE SPEETON CLAY OF YORKSHIRE. 



By John Leckenby, Esq., of Scarborough. 



The lowest beds of Speeton Clay in overlying contact with any inferior 

 stratum have never been found in Filey Bay, but a little to the south 

 of a point where it is first exposed Lias " scars " exist with Ammonites 

 communis and A. Walcotti in situ, showing great upheaval or disturb- 

 ance, or else great unconformability here. 



L The lowest known beds of Speeton Clay, so called, consist of blue 

 clay, with seams of septarian nodules. In one of these seams, in beds 

 of a black claystone, specimens of ^-lm??io?uVes hiplext\\YQQ to four inches 

 in diameter are not unfrequent. This is the only fossil found in this 

 bed. 



2. Above this is a band of strong, slaty, brown clay, very ligneous 

 and peaty, containing remains of fishes only. Here was found the 

 unique Palceoniscus Egertoni, now in the possession of the Earl of 

 Enniskillen. Thickness 12 feet. 



3. Next we have a black shaly clay, containing large nodules like 

 the cement-stones, but not used as such. These nodules contain a 

 beautiful Ammonite, named by Mr. Bean A. evalidus, but no other 

 Mollusca 20 feet. 



4. Another band of strong clay, containing compressed Ammonites 

 and other shells, all too imperfect for discrimination. This band is 

 traversed at intervals by seams of septarian nodules. . . .50 feet. 



5. A thin seam of impure clay, with fragments of Ammonites and 

 Belemnites 1 foot. 



6. A stratum of dark-brown shaly clay, containing imperfect, com- 

 pressed, bivalve shells, and a seam of coprolitic nodules. . . 5 feet. 



7. Compact light-grey argillaceous stone, destitute of fossils ; 



forming a remarkable line of demarcation between the beds below and 



those succeeding 3 feet. 



8. Tough and almost pure clay, containing many of the characteristic 

 fossils of the Speeton Clay as under . 8 feet. 



