1858.] WOOD EED CEAG, 35 



only of a particular kind, or merely an alteration of the conditions 

 under which the deposits have been formed, is not of much im- 

 portance, as the broadest divisions in geological sequence are in all 

 probability only conventional, although necessary and most useful for 

 the purposes of study. I can only say that, whether the Lower Crag 

 be or be not entitled to be called Pliocene, — the Middle Crag, Newer 

 Pliocene, — and the Mammahferous or Upper Crag, Pleistocene, — 

 they indicate great and successive changes ; the Coralline Crag having 

 been deposited in quiescent water with a facies of fauna different 

 from that of the Eed Crag ; while previously to the deposit of the 

 native bed at ChiUesford, the land must again have undergone a 

 subsidence. These differences denote changes of condition in those 

 localities, at least, during their depositions; and, as such, I have 

 considered the Red Crag to be a deposit of a distinct period. 



In regard to the Cetotolites of the Red Crag, when first deter- 

 mined by Prof. Owen, they were considered by that gentleman as 

 having been undoubtedly derived from the London Clay, and at 

 p. 542 of the 'History of British Fossil Mammalia' are the fol- 

 lowing words : — " that the fossil ear-bones and Cetacean teeth of the 

 Red Crag have been washed out of the subjacent Eocene Beds, is 

 probable from the fact of a CetotoKte having been discovered in 

 the London Clay itseK; and from fragments of other Cetaceous 

 bones having been obtained from the same formation. In the 

 Hunterian collection of fossils, I have determined some consider- 

 able fragments of bone to be Cetaceous : they were recorded to be 

 from Harwich Cliff, Essex, and were in the same completely-petri- 

 fied condition as the fossil ear-bones from the Red Crag." There is 

 no doubt of the fact of these Cetacean bones having been obtained 

 from the Harwich Cliff, but the inference that they were derived 

 from the London Clay does not appear to be a necessary one. 

 The formations in this locality are the same as those occurring on 

 the eastern side of Suffolk, the basement portion of the Coast as far 

 as Woodbridge is the London Clay, capped by the Red Crag and 

 sands of more modem date ; and, although the Crag is no longer 

 seen at Harwich, in consequence of the encroachments of the sea, 

 it is the spot whence Dale in 1730 obtained all his Crag fossils, and 

 therefore the Whales' bones there found are no better evidence of 

 Eocene derivation than those obtained at Felixstow or at Sutton. 



The Whales' bones that have lately been obtained in great abun- 

 dance are all or nearly all found at the basement portion of the 

 Crag deposit, in association with the phosphatic nodules and fish- 

 teeth that have been presumptively considered as derivative fossils 

 of the London Clay ; and, whether these Cetotolites or Cetacean 

 remains were really derived from the Older Tertiaries, or from some 

 more modem period, their accumulation in such large numbers in 

 so comparatively confined a spot indicates strongly their derivative 

 nature, and that they do not strictly belong to the deposit in which 

 they are now found. We must therefore seek for evidence as to 

 whether the Older, the Middle, or the Newer Tertiaries be the 

 formation whence they were derived. 



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