Clii PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



direction the point of Taninge or the Dent de Marcely to the height 

 of 7000 feet. 



He then compared the coal of Matringe with the neighbour- 

 ing bed of Taninge, and found the fossils of the lower Lias in the 

 massive calcareous deposit over the Matringe deposit of coal, and 

 determined that this mass is the same as that which covers the 

 coal of Taninge. He therefore concludes that both these carbona- 

 ceous deposits are covered by deposits which from their fossils ought 

 to be considered Liassic, and cannot therefore be considered in any 

 respect as Nummulitic. M. de Heer has examined the specimens of 

 fossil plants collected by M. Favre ; and, though he differs in some 

 respects from M. A. Brongniart and M. Schimper as to the species, he 

 quite agrees with them in considering that they are truly Carboni- 

 ferous ; and, on his part, M. Favre maintains that the stratification is 

 in accordance with that opinion. To the north of Taninge the num- 

 mulitic formation does not appear ; but to the south it is found at 

 between three and four miles from that town ; and M. Favre ima- 

 gines that its occurrence there has probably led M. Sismonda to class 

 the coal with it, though in reality there is no connexion between 

 the two formations. Without doubt, the obscurity of the stratifi- 

 cation of the Alps must always render it very difficult to escape from 

 error: M. Favre considers, however, that he has fully shown that, 

 in the Alps, the more ancient Jurassic strata are more highly deve- 

 loped than the nummulitic. 



He then corrects the statement of II. Elie de Beaumont, by show- 

 ing that the coal of Darbon, like that of the Cornettes de Bize, be- 

 longs to the upper Jurassic, being distinguished from that of Taninge 

 by its fossils ; and the observations of M. Delaharpe and M. Studer 

 are in conformity with his own. Again, the coal of the Commune 

 d'Arrache, near the hamlet of Pernaut, described by MM. Sis- 

 monda and Elie de Beaumont, really belongs, as stated by those 

 geologists, to the nummulitic formation; and it is therefore no 

 matter of surprise not to find in it coal-ferns. The deposits of the 

 Diablerets and Entrevernes are of the same age ; and as M. Favre 

 has noticed eight localities where this carbonaceous deposit is found, 

 and has traced it from Savoy into the centre of Switzerland, it can- 

 not, he observes, be considered a very local deposit. This determi- 

 nation of three distinct carbonaceous deposits in successive epochs is 

 certainly more in harmony with nature than the supposition that 

 the coal-plants had resisted all the physical changes which must 

 have elapsed in so long an interval as that between the Carboniferous 

 and Nummulitic epochs ; and we may admit that M. Favre has not 

 broken a lance, to use his own words, in favour of the value of fossil 

 botany as an indication of the age of deposits, in vain. 



I may mention, that Signor Cocchi has informed me that he is 

 about to resume his researches on the geology of Tuscany, of which 

 I took notice in my last address, and has promised another visit to 

 England at no distant period to communicate the results of his 

 inquiries into fossil fishes. But what I am particularly desirous to 

 bring before you is the Report on the Geological Survey of Canada, 



