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XXII. — observations on the Locality of the Hyracotherium. 

 By WILLIAM RICHARDSON, Esq., M.A., F.G.S. 



[Read December 18th, 1839.] 



AN the year 1829, when I first became acquainted with that portion of the London 

 clay formation which extends on the northern coast of Kent from Whitstable to 

 Heme Bay, it presented, with exceptions too unimportant for notice, one uniform 

 lithological aspect. The cliffs or escarpments on this line of coast, proceeding 

 from Heme Bay westward, are Hampton Cliff, Studd Hill, Swale Cliff, or rather 

 cliffs, for there are many, and Tankerton Cliff. Hampton Cliff attains an eleva- 

 tion of 1 00 feet, Studd Hill of fifty feet, and the Swale Cliffs average a similar alti- 

 tude; while Tankerton Cliff, with its undulating outline, terminating at Whitstable, is 

 about sixty feet in height. These several cliffs, in the year 1829, could be at once 

 identified as members of the London clay, as well by their mineral aspect as by 

 their organic contents. They were capped with vegetable mould to the extent of 

 one or two feet ; beneath which were three or four feet of yellow marl or brick 

 earth, containing rolled and angular flints, numerous mammalian remains, and 

 fossils derived from secondary strata. The flints and fossils were confined to the 

 upper portion of this bed, and the marl to the lower. To this marl succeeded, 

 in the descending order, the London clay, consisting of a dark brown incohe- 

 rent rock, abounding in septaria, selenite and wood, completely pyritized. The 

 fossil contents of the clay were also similar, or nearly so, in these several cliffs, 

 consisting of the teeth and vertebrae of fish, nautili, and other marine testacea 

 characteristic of the London clay, encrinal and pentacrinal stems, and the usual 

 crustaceous remains. In none, however, did I ever discover a solitary fragment of 

 the reptiles which have rendered the neighbouring cliffs of Sheppey so celebrated. 

 At the period of which I am writing, 1829, with the exception of slender frag- 

 ments of the trunks and branches of trees, fossils of the vegetable kingdom were 

 rare. 



Such was the condition, lithological and fossil, of these cliffs in the year 1829, 

 and such, with the exception of Studd Hill, are the characters which for the most 



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