186 Geological Olservations. 



agrees with the old red sandstone of Werner, the first of the 

 floetz series. The only legitimate conclusion, therefore, that can 

 be drawn from the fact above stated is, that the same fossils 

 which occur in transition rocks may also occur in those of the 

 first floetz series. 



If then we regard the mountain limestone as a member of the 

 first floetz series, it may be asked, Does transition limestone oc- 

 cur in England ? Geologists in several places have described 

 limestone which certainly widely differs from mountain lime- 

 stone ; and in several instances such limestones appear decidedly 

 transition. The limestone of Plvmouth Dr. Bergcr describes 

 of a blueish colour frequently intersected by veins of calc spar, 

 of a crystalline grain and destitute of organic remains ; though, 

 according to a notice in the Annals of Philosophy for February, 

 it contains shells in quarries at Stonehouse-hill and dock-yard. 

 Dr. Berger s})eaks in the most decided manner of its being trans- 

 ition ; and Dr. Thomson, in his Account of the Geology of 

 Cornwall, savs that it is associated with clay-slate, and " that 

 there can be no hesitation in considering it transition " Mr. 

 Horner, in his Account of the Geology of the Malvern Hills, has 

 described a formation of limestone resting on the west part of 

 the range. This I have seen ; and it ajjpears to me very different 

 in its general structure from the mountain limestone; which, as 

 far as I have seen, generally occurs in strata of considerable mag- 

 nitude : the strata however of the Malvern limestone seemed to 

 me never to exceed the thickness of a foot or a foot and a half, 

 Mr. Horner considers them as decidedly transition ; and as it 

 appears that they rest in the sienite of the Malvern Hills, which 

 is indisputably transition ; and since, as Dr. Prichard informs us, 

 they dip luider the old red sandstone of Herefordshire, — there 

 can, I think, be no doubt of their being entitled to this deno- 

 mination. In a paper of Mr. Horner's lately read before the 

 Geological Society, and of which Dr. Thomson has given an 

 extract in his Annals of Philosophy, the Quantock Hills are de- 

 scribed as being composed of a gray wacke formation alternating 

 with strata of clay-slate. Within the latter strata beds of lime- 

 stone are included, which are therefore manifestly transition. 

 Mr. Allan, in his Remarks on the Transition Rocks of Werner, 

 (Thomson's Annals, p. 416, vol. i.) says that the limestone at 

 the lakes of Windermere and Coniston, which contains organic 

 remains, is transition. 



In Thomson's Annals of Philosophy, vol. v. p. 456, there is 

 a notice of a paper of Mr. Buckland's, read before the Geolo- 

 gical Society, On the Rocks situated to the east of Appleby, 

 between Malmerly and Morton in Cumberland; in which it ap- 

 l)ear5 that these rocks are chiefly composed of greenstone and 



slate. 



