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nected with the vegetable remains 

 found in the London clay, are 

 those which have been observed in 

 the Isle of Sheppey : the quantity 

 of fruit or ligneous seed vessels is 

 extraordinary. Mr. Crowe, of 

 Faversham, has procured from this 

 productive situation a very large 

 collection, from which he has 

 selected 700 specimens, none of 

 which are duplicates, and very few 

 of which agree with any known 

 seed-vessels. Among these are 

 many which appear to belong to 

 tropical climates. Mr. Bowerbank 

 observes, " among the numerous 

 and highly interesting fossils found 

 in the London clay, none are more 

 abundant than the remains of fruits 

 and seeds." He also states that 

 during a few years 120,000 fruits 

 and seeds have passed through his 

 hands. In these beautiful remains 

 of an extinct flora, the minute and 

 delicately formed vegetable tissues 

 are preserved in the most perfect 

 manner. As regards the extent of 

 the London clay deposit, it forms 

 the superior stratum of the chalk 

 basin of London, except where it is 

 partially covered by the sands of 

 the upper marine formation, or by 

 alluvial sands, gravel, and loam. 

 It extends uninterruptedly and in 

 a south-westerly direction from 

 Orford, on the coast of Suffolk, 

 about 20 miles north-east of Har- 

 wich, and a little to the north of 

 Ipswich, in that county ; to the 

 south of Coggeshall, and thence to 

 Eoydon, in Essex ; from this place 

 it turns nearly south, extending to 

 a little on the west of Edmonton, 

 in Middlesex, and thence in a 

 north-westerly direction by Chip- 

 ping Barnet and South Mims to the 

 north of Eidge Hill ; here it turns 

 suddenly southward, and afterwards 

 south-west by Harfield and Ux- 

 bridge to the eastward of Colebrook ; 

 it then passes away nearly west, 

 crosses the Thames by Windsor 



and Twyford, and passes to about 

 three miles south-west of Beading, 

 which is its most western point. 

 It then turns to the south-east, in 

 an irregular line, to within a very 

 short distance of Farnham and 

 Guildford, in Surrey, and on by 

 Epsom, and a little to the north of 

 Croydon to Deptford, in Kent. 

 The London clay, therefore, con- 

 stitutes a very large part of the 

 soil of Suffolk, nearly the whole of 

 Essex, quite to the sea, the whole 

 of Middlesex, and portions of Berk- 

 shire, Surrey, and Kent. In this 

 last county it shows itself on the 

 northern side of the Medway; it 

 constitutes the whole of the Isle of 

 Sheppy, rapidly disappearing under 

 the force of the waves, the cliff 

 from Whitstable to Reculver, and 

 extends nearly to Canterbury, and 

 thence to Boughton Hill. In the 

 chalk basin of Hampshire this 

 deposit is also extensively devel- 

 oped, forming the whole line of 

 coast from Worthing in Sussex to 

 Christchurch in Hampshire, ex- 

 tending thence inland by Eing- 

 wood, Eomsey, Fareham, and to 

 the southward of Chichester to 

 Worthing. It is found also in the 

 Isle of Wight, thrown with the 

 subjacent chalk into a nearly verti- 

 cal position. With this exception, 

 the beds of the London clay are 

 nearly horizontal. 



It has been remarked, that if 

 the description of the Paris rocks 

 had not preceded that of the coun- 

 try round London and of the Isle 

 of Wight, it never would have been 

 considered that the Plastic clay was 

 separated from the London clay, 

 but rather that they constituted 

 different terms of the same series. 

 The London clay belongs to the 

 eocene period. 



LONGICO'BNES. (from longus and cornu, 

 Lat. long horned.) A family of 

 insects in Cuvier's arrangement, 

 and so named from the length of 



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