Proceedings of the British Association. 129 



ceous and tertiary systems of the S.E. coast of the Isle of Wight. 

 Measurements of all the strata, both tertiary and cretaceous and 

 tables of their fossil contents, were also laid before the meeting. Re- 

 viewing the strata deposited from the cessation of the Wealden to 

 the prevalence of a fresh-water eocene formation in this locality, the 

 authors laid stress on the following facts in the local history of 

 organized nature during that long period : — That the seas in which 

 the lower greensand was deposited occupied the area described, in 

 consequence of the sudden subsidence of the great Wealden lakes, 

 and presented from the very commencement a Fauna which was 

 truly marine, and most of the members of which began their exis- 

 tence with the commencement of the cretaceous era in England. 

 Almost all the animals which appeared were such as were new to the 

 oceanic Fauna, but among them were many forms representative of 

 other species which had existed in the oolitic ocean. Secondly, 

 that this Fauna continued, though apparently diminishing in con- 

 sequence of the extinction of species from physical causes, until 

 the commencement of the deposition of the gault, when a new 

 series of animals commenced, among which a few previously existing 

 species lived on, but the greater part were either representative or 

 peculiar forms. The same system of animal life appears to have 

 continued throughout the remainder of the cretaceous era in this 

 locality, although great differences in the distribution of species, and 

 many species local in time occur, depending on the very great change 

 in the mineral conditions of the sea bottom during this epoch. The 

 chalk formation especially presents many peculiar species, owing 

 rather to the zone of depth in which they lived, than a new zoolo- 

 gical representation in time. The authors called attention to the 

 assemblage of minute corals, sea-urchins, terebratulae, and Spon- 

 dylus spinosus, in that part of the Culver Section at which is seen 

 the junction of the chalk with flints and the hard chalk, as corres- 

 ponding to the characters which mark a very deep sea Fauna at the 

 present period. Thirdly, that in the tertiary formation which 

 succeeds there is an entirely new Fauna, distinct as to every species 

 in this locality, though elsewhere connected with the cretaceous 

 strata by the presence of that remarkable mollusk, Terebratula 



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