148 Geological Society, 



Count Keyserling, led both that gentleman and the author to the 

 same conclusion. Among the numerous fossils they there collected 

 were many identical with, or analogous to, Neocomian species, par- 

 ticularly in that portion of the coast section so minutely described 

 by Dr. Fitton and Sir John Herschel, viz. between Black Gang 

 Chine and Atherfield rocks. Mr. Murchison observed that there 

 seemed to be a gradual zoological as well as lithological passage from 

 the Wealden beds below into the greensand and shales above them ; 

 for although the shale with Cypris occurs immediately beneath the 

 marine deposit of Atherfield rocks, as remarked by Dr. Fitton, 

 another band of flagstone with marine shells (^Ostrea and Terebra- 

 tula) also occurs beneath these uppermost beds of Cypris. In the 

 still lower strata, however, we lose all traces of such marine alter- 

 nations, and the whole becomes one great freshwater deposit. A 

 similar phccnomenon is seen in the southern part of the section at 

 Red Cliflf, extending into Sandown Bay, where beds with Cypris are 

 intercalated between oyster beds. These alternations are indeed 

 what we might expect to find, provided a former depression of the 

 surface had converted a lake into an estuary, and subsequently into 

 a marine baj\ But notwithstanding the natural connexion be- 

 tween the Wealden and the lower greensand, it does not follow that 

 the two formations ought to be merged in one system or natural 

 series. Dr, Mantell as long ago as 1822 pointed out the analogy 

 between the animals of the Wealden and those of the Stonesfield 

 beds ; and more recently Professor Owen has carried it out much 

 further. Professor Agassiz has pronounced the Ichthyolites of the 

 cretaceous system to be entirely dissimilar from those of the Wealden. 

 Mr. Murchison inquires, where are we to draw the line of sepa- 

 ration which shall indicate jirecisely in our own country the base of 

 the Neocomian of foreign geologists, or in other words, the base of 

 the great continental cretaceous system ? On this point he remarks 

 that some small amount of compromise may eventually be found de- 

 sirable ; for whilst we have on the one hand full right to infer that 

 the larger portion of the Wealden must be classed in the oolitic 

 series, further inquiry may convince us that its uppermost part is of 

 the same age as the lowest Neocomian strata ; and thus we may 

 connect that portion of it with the cretaceous system. In the mean 

 time it is quite clear that a great part of the Neocomian is absolutely 

 the lower greensand itself. This view is confirmed by Count Key- 

 serling, who has identified fossils from the Neocomian strata of Kys- 

 lavodsk in the Caucasus, with specimens collected by him in com- 

 pany with Mr. Murchison in the lower greensand of the Isle of Wight. 



Api'il 26. — A paper was read " On the upright Fossil-trees found 

 at diflferent levels in the Coal strata of Cumberland, Nova Scotia." 

 By Charles Lyell, Esq., F.G.S. &c. 



The first notice of these fossil trees was published in 1829 by 

 Mr. Richard BroMn, in Haliburton's ' Nova Scotia,' at which time 

 the erect trunks are described as extending througli one bed of 

 sandstone, twelve feet thick. Their fossilization was attributed by 



