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3. The fossils under the breccia seem to have been quietly deposited 

 by a sea that stood several feet higher than the present Mediterra- 

 nean. To explain this difficulty, some authors imagine that the Me- 

 diterranean has sunk, by forcing its passage through the Straits of 

 Gibraltar ; but this supposition the author conceives to be impro- 

 bable. 



II. 1 . — Tertiary rocks consisting of sand, sandstone, and a conglo- 

 merate of various rolled pebbles, shell marl, calcareous gritstone 

 and breccia, and gray marl, occupy an extensive area on the west 

 and north-west of Nice. 



The shell marl here mentioned is that which Brocchi has described ; 

 and it contains, in the Sub-Alps, the same fossils as in the Sub-Appe- 

 nines. 



In the calcareous breccia are angular pieces of the contiguous 

 limestone and dolomite perforated by lithodomi j adhering to which 

 are sometimes found the lower valves of spondyli, quite perfect, not- 

 withstanding the delicate texture of their edges. The cement con- 

 tains three species of pecten ; — with remains, perhaps, of a Saurian. 

 Care must be taken not to confound this latter breccia, which rises 

 more than a thousand feet above the sea, with the diluvial breccia 

 above described. 



On reviewing the tertiary beds, the author remarks in their probable 

 history three distinct epochs ; viz. two of repose, and one of violent 

 disturbance. 



2. The Secondary rocks of Nice consist of two great formations ; 

 the upper one composed of siliceous, argillaceous, and calcareous par- 

 ticles intimately mixed, but in very variable proportions ; some of the 

 beds abounding in green grains ; which circumstance, together with 

 the nature of their fossils, induces the author to rank the formation 

 to which they belong with the green-sand of England. Nummulites, 

 however, which are rarely found in the green-sand of this country, 

 are found plentifully in that of Nice. The strata are very much dis- 

 turbed and contorted • so that an unguarded observer might often 

 suppose them to be inferior to rocks on which they are in reality in- 

 cumbent. 



The green-sand is succeeded by a lower formation, which the author 

 refers to the Jura-limestone or oolite. In this he has found, occasion- 

 ally, terebratulse ; in addition to which, Mr. Allan states that it 

 contains ammonites, pectens, an echinus, and, near the lighthouse at 

 St. Hospice, numerous corals. In mineralogical character, this stra- 

 tum is very unlike the English rocks which it is supposed to repre- 

 sent; its principal members being compact limestone, with occasion- 

 ally, flint, dolomite, and gypsum. The dolomite and compact lime- 

 stone are intimately connected ; but the connection of these two 

 beds with the gypsum is less evident. At Sospello the gypsum 

 affords numerous small crystals of carbonate of magnesia or dolo- 

 mite ; but both these substances are found in too many formations 

 to be considered as characteristic. 



The strata to which the compact limestone, dolomite and gypsum 

 of Nice are most analogous, are those of the Tyrol, Carinthia, Stiria, 



