1859.] WKIGHT INFEKIOB OOLITE. 29 



" grey limestone" or the so-called " Bath Oolite," which repre- 

 sents the Humphnesianus-zone of the Inferior Oolite. 



No. 10. Grey limestone rises on the sea-shore, and may he easily 

 overlooked if it happens to be covered with debris, although it is 

 always visible in the cliff, from which fossiliferous fragments are 

 constantly falling on account of the weathering of the underlying 

 shales. 



The grey limestone at Gristhorpe forms a very inconsiderable 

 stratum, about 3 feet in thickness ; but at the White Nab and at 

 Cloughton "Wyke, and in Haiburn and Stainton Dale cliffs, it attains a 

 considerable thickness, and admits of a general division into six beds, 

 which, in descending order, may be thus enumerated * : — 



a. Alternate layers of argillaceous oolite and nodular ft- in. 



ironstone. About 3 



b. Dark clay with Monotis and GerviUia. From 8 inches to 1 



c. Nodular ironstone, many of the nodules containing 



Ammonites Blagdeni, &c From 6 inches to 1 



d. Hard, dark, ferruginous clay, with Saurian bones and 



fossil shells 2 



e. Close-grained greyish oolite, in parts iron-shot 5 



/. Hard, blue, thick-bedded limestone, used for building 



From 12 to 18 



The inferior layer of a at Cloughton contains Pema rugosa, I ioldf., 

 and other shells, b is well exposed on the shore near Scarborough, 

 where QervUlia acuta, Phil. ( Q. consohrina, d'Orb.), forms the domi- 

 nant shell. Many of the large nodules of c contain Ammonites 

 ffiiiit/ifiriesianus, A. Blagdeni, and A. Braikenridgii. Saurian bones 

 ( /'/. siitsanrus and Ichthyosaurus) have been found in d, near Scar- 

 borough ; and the same bed at Cloughton affords many fossil 

 shells. Few, if any, fossils have been found in e ; and the lower 

 ami middle portions of/ are equally unproductive ; the upper part 

 of/ contains Behmnites giganteus, Schloth., Myacites talceiformit, 

 Phil., Oressh/a decurtata, Phil., Chemmteia Scarburgensis, Lye., and 

 the long mnrioated spines of Bhabdoeidaris maxima, Goldf. The 

 White Nab and Cloughton are the beet localities for obtaining fossils. 

 Many of the beds are exposed at the south side of Scarborough Bay 



at low water; and nearly Opposite the Cliff Bridge, at low tides. 



an anticlinal axis is visible, extending N.K. to B.W., by winch the 

 beds of grey limestone suddenly incline r> to the Bouth, and the 



Kellowaj Bock and Oxford Clay of tin i Hill dip to the north. 



Fossils from th, Qrey Limestone, in Mr. Leekenby'a Cabinet, Sec. 

 Belemnitea Bjffanteaa, Qehloth. Ammonites I'arkinwni. s,.w. 



Ammonites Iluinphricsinmui, 



Blagdeni, Sow. 



Braik<iiriilt:ii, flbw. 



baroagfa Ifaaeam. This roeoimea 



was collected in the upper I 



the grey lime-tone afl White fob.) 



* Profeaaor Williamaon baa groan ■ mod i oriptum of the " I 



Limestone," with like aobdiviaioiia, in bia raloable ]m|>. r • < ho thediatribnl 



I'V.-mI Remain! 00 tli" York-hiiv I 



p 223. 



