[NTEODUCTTON. 17 



occurring in Yorkshire only at Cloughton, near Scarborough, though Wrighl 

 had already recorded it from the Cornbrash of Scarborough. 



20. SoAEBOEOUGH. — The Cornbrash is here no longer to be seen. A solitary 

 block of it amongst the debris on the north side of the Castle was all I could 

 recently find. In Bean's days (1838) he described its range as easily observed ; 

 and in Wright's time (1800) he states "the rock has been worked out and will be 

 shortly covered up." When I first knew the locality the shore was largely strewn 

 with its blocks, mingled with those of the Kellaway rock — now there is a roadway 

 over all. We arc, therefore, entirely dependent on the past. Fortunately the 

 matrix, of purplish oolitic aspect, is very distinct from the only other fossiliferous 

 zone here, the yellow Kellaway Sandstone, and when recognised is absolutely 

 decisive. The fossils here have one great advantage over almost all localities in 

 the south : they are autochthonous, and not mixed with any deposit made during an 

 earlier epoch. 



30. Cayton Bay. — in this bay the position and composition of the Cornbrash 

 arc perfectly clear. At the north end it is faulted and spread out on the 

 foreshore, but at the south end the following section is seen : 



Kellaway Sandstone in the cliff — 



1. Shales with Aviaila bramburiensis, Crustacea, and Macrocephalites 



2. Hard shaly band full of Ostrea marshii on the surface 



3. Hard ferruginous dogger hand, with Macrocephalites forming a strong scar 



4. Soft gritty rubble bed full of broken shales 

 a. Pale clay with a sharp boundary above and no sign of a fossil. 



The inclusion of the Avicula-sh&les with the ordinary fossil-bearing masses 

 below is justified by the occurrence of Macrocephalites in them, and confirmed by 

 the overlying rocks containing the three characteristic Ammonites of the next /one, 

 modiolaris, Icoenigi, and gowerianus, but when this development is compared with 

 that at Weymouth we learn the variation of lithological characters in general. 

 Here the upper part of the Cornbrash is shale, at Weymouth largely limestone ; 

 while the overlying beds are here of sandstone, at Weymouth largely clay. 



In this locality the bed here included with the Kellaway rock, being seen 

 in situ, has not always been distinguished from the Cornbrash, but it is darker 

 in colour, with lighter oolitic grains, and the fossils are not always identical. 



Ft. 



in. 



8 



0? 







8? 







10 







8 



