498 Geological Society. 



The portion of the coast to which this paper immediately refers is 

 called the Easington Height, situated between Whitby and Redcar, 

 and presents the following details : 



INFERIOR OOLITE. 



Upper Lias Shale. . 



Shale 35 feet 



Hard or cement stone bed 25 



Shale, containing nodules of ironstone 90 



Jet rock 20 to 30 



Hard compact sandy shale 30 



about 200 



Marlstojie. 



Thin seams of shale, alternating with hard iron- 

 stone bands, a foot thick 25 



Sandy shale, with beds of dogger 63 ? 



Alternating beds of calcareous sandstone and 



sandy shale 40 



Shalysandstone,passinggradually into the lower 



lia's shale 30 ? 



160 



Lower Lias Shale 150 



The beds of shale superior to the jet rock are characterized by the 

 presence of Nucula ovum, Orbicula reflexa, Plagiostoma pectinoide, 

 Ammonites communis, A. heterophylhis, A. Jimbriatus, A. Walcottii, 

 A. subcarinatus, A. angulatus, A. crassus, A.Jihulatus, A. suharmatus, 

 A.Lythensis, A. Boulbiensis, A.annulatus, Nautilus astacoides, and 

 Belemnites elongatus. The species gradually decrease in abundance 

 on approaching the jet rock, and the specimens which do occur in 

 that stratum are stated to be smaller than in the higher beds. The 

 jet rock contains a peculiar suite of Ammonites, viz. A. elegans, A. sig- 

 nifer, A. elegantulus, A. exaratus, A. Mulgravius, A. concavus, and 

 A. ovatus. It is also distinguished by containing the remains of the 

 gavial-snouted crocodile. With respect to the relative abundance of 

 the fossils, Mr. Hunter observes that where they occur in the greatest 

 number Ihey are smallest in size. 



The beds situated between the jet rock and the marlstone are very 

 poor in fossils. 



The marlstone series is distinguished not only by a change in the 

 species, but in the preponderance of bivalves and the comparative ra- 

 rity of .Ammonites ; the characteristic fossils being Avicula cygnipes, 

 A. in(equivalvis, Pecten sublcevis, P. aquivalvis, Pullastra antiqua, se- 

 veral species of Terebratula, Cardium truncatum, Modiola scalprum. 

 The species of Ammonites are few, A. vittatus occurring about the 

 centre of the series, and A. maculatus at the junction with the lower 

 lias shale. 



In conclusion, Mr. Hunter states that the difference between the 

 distribution assigned to the fossils by himself and other authors may 

 be owing to the prevalent practice of collecting fossils from subsided 

 masses, and not from undisturbed portions of the cliffs. 



