56 Bibliographical Notices. 



the early inquiry respecting the true relations of the Wealden strata, 

 and which are not perhaps so fully known as they deserve. To 

 Dr. Fitton we are not only indebted for the term " Hastings sands," 

 but also for pointing out their geological and palseontological rela- 

 tions to the other beds. In 1822 these sands were described as 

 " Iron sands*' by Dr. Mantell (Fossils of the South Downs, p. 24), 

 and considered in one place (p. 37) to be separated from the Weald 

 clay by the Tilgate limestone ; while in another this limestone was 

 identified with the Purbeck (p. 299), and is there presumed to have 

 been protruded through it, where it is also stated, " whether they 

 (the Iron sands) are of freshwater or of marine origin, has not been 

 satisfactorily determined. The term "Iron sand" was also used by 

 Buckland, Greenough, Conybeare, and Phillips ; and it was " the 

 sand and sandstone beneath the oak-tree clay" of Smith. Webster, 

 in his * Letters to Sir H. Englefield,' described them as " ferruginous 

 sands," including under this name also the Weald clay and Lower 

 green-sand, and considered the Purbeck beds as constituting the lowest 

 strata of the Isle of W T ight. Dr. Fitton, in 1 824, clearly pointed out 

 that the two sands were distinctly separated " by a stratum of clay 

 precisely corresponding, both in situation aid in the fossils which it 

 contains, with the Weald clay of Kent and Sussex. It is the inferior 

 of these sands alone which is the equivalent of the Hastings beds ; 

 and these constitute the lowest formation visible in the Isle of Wight" 

 (Annals of Philosophy, 1824, vol. viii. p. 367); and further, that 

 the organized productions of the Lower greensand (Shanklin sand) 

 were all marine, but those of the Hastings sands, almost exclusively, 

 of freshwater origin {ibid. p. 379). Nor should the observations 

 and deductions of Sir C. Lyell at that time be overlooked, respecting 

 the order of the strata below the Chalk (communicated to Dr. Man- 

 tell, July 1822), and which are frankly acknowledged by Dr. Fitton. 



Amongst the additions to the Secondary rocks, the notice of the 

 extension of the bone-bed is an interesting feature. Some other 

 points in the oolitic strata require further investigation, more espe- 

 cially as regards the nature, character, and equivalents of the Lower 

 Oolites in the central counties of England : there are good reasons 

 for believing that the slates of Stonesfield and Collyweston alluded 

 to (pp. 5 10, 5 16) are not synchronous ; they have few organic remains 

 in common, and the Collyweston slates appear to be low down in the 

 Inferior Oolite, or at least underlie beds containing some of the 

 characteristic fossils of that stratum in the west of England. 



The Trias and Permian are retained, as before, in one chapter, but 

 their geographical extension is more fully described, and the researches 

 of Murchison, Ramsay, King, and Howse, on these deposits noticed. 

 The lecture on the Carboniferous system, upon which the editor 

 has expended much time, labour, and thought, will be read with 

 considerable interest, as containing new and important matter, clearly 

 put and concisely arranged, so as to afford a general view of the 

 structure, conditions, nature, and probable mode of accumulation of 

 this important portion of the geological series ; the student being 

 especially referred to numerous valuable papers treating of the nature 



