MANTELL ON FRUITS FROM THE CRETACEOUS ROCKS. 51 



tion from the present shore to near the summit, are evidently the 

 result of the long-continued action of the sea. 



In conclusion, I have to observe that these disturbances, of which 

 we have such clear proofs, form but a portion of those to which the 

 rock has been subjected ; they give us in chronological order the 

 geological history of the elevated part, but throw no light on the 

 relative antiquity of those disturbances which have lifted up the 

 beds at its western base to a vertical position, or elevated those at 

 the south with an inclination opposite to that of those at the north, 

 or caused the great escarpment of the western slope of the moun- 

 tain. 



With regard to the period in which the upheavals attended with 

 rupture and dislocation of the strata took place, we have scarcely 

 any evidence ; those shells which were deposited before they ceased 

 have the appearance of being recent, but the number of species is too 

 few in the beds deposited before the last of these disturbances to af- 

 ford any certain inferences as to their age. On the other hand, we 

 have ample evidence to prove, that, since the testaceous fauna was 

 the same as at present, many movements both of elevation and de- 

 pression must have taken place. 



Description of some Fossil Fruits from the Chalk Formation of the 

 South-east of England. By Gideon Algernon Mantell, 

 LL.D., F.R.S. &c. 



[Read January 18, 1843.] 



Plate II. 



The small number of plants hitherto discovered in the Chalk forma- 

 tion of England renders any addition to the Cretaceous flora import- 

 ant ; I am therefore induced to lay before the Society descriptions 

 and figures of three fruits from the Chalk and Lower greensand of 

 Kent and Sussex, that an authentic record may be preserved of 

 these unique and interesting relics. 



1. Zamia Sussexiensis, Mantell. Plate II. fig. L 

 From the lower greensand at Selmeston, Sussex. 



More than twenty years since I discovered a deposit of calca- 

 reous wood in the strata of greensand near Willingdon, a village 

 about three miles to the north-west of Eastbourn, in the county of 

 Sussex : a similar accumulation of fossil wood occurs in a sand-bank 

 in the adjacent parish of Selmeston, at the junction of the lower green- 

 sand with the gault, and is described in my ' Fossils of the South 

 Downs' (p. 76). The specimens collected from these localities con- 

 sist of waterworn fragments of stems and branches, which are gene- 

 rally more or less perforated by boring moUusca. 



The structure of the wood is decidedly coniferous ; transverse 

 sections present concentric circles and medullary rays, and a reti- 

 culated surface composed of distinct cellules, varying in form from 



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