350 Mr. R. C. Taylor on the Geulogy of East Nojfulk. 



ceased at the epoch which invested the whole with their dilu- 

 vial covering. 



That the crag shells and their accompaniments form a com- 

 paratively local deposit, like some other formations, is evident. 

 Its existence and its peculiarities, nevertheless, indicate a di- 

 stinct geological asra. 



Let us recapitulate the remarkable facts, by which, in this 

 case, the questions of identity and general continuity are de- 

 termined. 



A district, bordering a hundred miles upon our eastern 

 coast, is occupied by an ancient marine deposit, continually 

 changing its aspect, yet constant in its peculiar characters, and 

 ahvavs to be understood by unerring data : now ajipearing 

 as a ferruginous sandstone, then in compact clay, and again 

 considerably indurated ; sometimes blended in a mass of ex- 

 tinct zoophites, sponges and alcyonites, forming a soft rock; 

 oftener an irregularly accumulated mass of decomposed and 

 broken littoral shells, loosely imbedded in sand like an ordi- 

 nary sea beach, yet accompanied with the remains of unknown 

 animals. Sometimes forming the substratum of a considerable 

 area ; or, overwhelmed beneath the debris of older strata, only 

 detected at intervals. At one point exhibiting groups of shell- 

 fish allied to those of the neighbouring sea, and at another 

 composed of numerous genera, which are neither to be recog- 

 nized living in any part of our globe, nor assimilating to the 

 fossil shells of other formations. Can it be doubted then, that 

 we must look to an earlier epoch in the geological history of 

 our earth ; to a period prior to that in which our diluvial 

 eastern counties received their existing shape and covering ; 

 and to other, but not less extraordinary operations upon 

 their antediluvian surfaces, than those to which Mr. Rob- 

 berds's views would limit us, in accounting for the phajnomena 

 to which he invites our attention, and of which 1 cannot but 

 consider an erroneous application has been made ? 



I have been led to introduce this sketch of the most remark- 

 able deposits above the chalk, because they have been hi- 

 therto neglected ; and because it was desirable to elucidate, 

 with precision, the geology of the limited district to which 

 these observations are directed, — so far, at least, as it bears 

 upon the assistance which the phsenomena it exhibits have 

 afforded to the peculiar views of Mr. Robberds. At this stage 

 of the inquiry, conclusions incompatible with those views are 

 unavoidably suggested by a consideration of the data here 

 supplied. 



Enough has been advanced, to withdraw from inferences, 

 apparently so unobjectionable, the very basis upon which they 



are 



