210 Sir R. I. Murchison on the Geological Structure 



posed, an upper member of the cretaceous rocks, but really represents 

 the true eocene. The adoption of this view, which it is supposed all 

 palaeontologists must adhere to, seems already to be also in great 

 part taken by M. Boue, in opposition to his former opinion. In 

 reviewing the physical relations of the upper secondary and lower 

 tertiary rocks of the Alps, it is made manifest, that the independence 

 of any one member of this succession cannot be assumed from its 

 unconformability to others in certain localities ; inasmuch as such 

 appearances are proved to be local pheenomena only, by a more 

 general survey which detects the order to be unbroken and conti- 

 nuous. In the Alps therefore, as in Russia, where deposits of several 

 ages are conformable, the limits of formations can alone be defined 

 by their imbedded organic remains. 



The author next developed the true age of the " Molasse and Na- 

 gelflue" of the northern portion of the Alps. Citing the researches 

 of Prof. Studer, M. Escher and others, he showed that the axis or 

 older part of these tertiary deposits was usually removed to some 

 distance from the higher ridges of cretaceous and eocene rocks, and 

 consisted of freshwater strata ; that the central or marine accumula- 

 tions are from their fossils (as collected in the Cantons St. Gallen 

 and Berne) of sub-Apennine or pliocene age, and that the great over- 

 lying portion of molasse and nagelflue, which frequently (owing to 

 enormous dislocations) seems to dip under the older rocks, out of 

 which it has been formed, is again, as far as can be ascertained, of 

 terrestrial and freshwater origin. Following these deposits in as- 

 cending order to their outermost and superior zone, they are found 

 to be surmounted by the well-known lacustrine formation of CEnin- 

 gen, formerly described in some detail by the author*. The remark- 

 able feature of this deposit is, that although it has unquestionably 

 been formed long after pliocene marine deposits (in which shells 

 exist undistinguishable from those now living), its fauna and flora 

 consist entirely of lost species. The examinations of its quadrupeds, 

 chelonia and reptiles by Herman von Meyer and Owen, of its fishes 

 by Agassiz, and of its plants by Goppert, all lead to this conclusion. 

 Even in respect to the insects of Qilningen, Prof. Heer of Zurich 

 has recently satisfied himself that in a multitude of species which 

 he is about to describe not one is identifiable with a living form. 

 Hence Sir Roderick maintains, that the terms miocene and pliocene 

 cannot be correlatively deduced from submarine and terrestrial for- 

 mations ; since if this be done in Switzerland, types of lost terrestrial 

 species overlie existing marine forms. 



In concluding his observations on the Alps, attention was called 

 to the extraordinary contortions and convulsions they had undergone. 

 By diagrams of various transverse natural sections it was shown that 

 the Oxfordian, cretaceous, and eocene or nummulitic groups had 

 conjointly undergone such great flexures as in many instances to 

 produce absolute inversions, and in others great ruptures, both longi- 

 tudinal and transverse. Whilst the direction of the sedimentary 

 rocks is shown to conform to the axes of certain great ellipsoids 

 * See Trans. Geol. Soc. Lend. vol. iii. N. Ser. p. 277- 



