226 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [DeC. 13, 



numerous AlveoIintE. Whilst mounds of peperino (occasionally how- 

 ever containing nummulites) occupy the upper conical summits of 

 Monte Bolca, overlying the dislocated and variously inclined lime- 

 stones, true tertiary shells are seen both in the limestones of Monte 

 Bolca itself and of its neighbour Monte Postale. Among these shells 

 are Natica, Fusus, Buccinum, Ostrea and small Avicula, with Tere- 

 dina closely resembling the T. personata of the London clay. We 

 have thus abundant proof of the age of this deposit ; but when the 

 fishes are appealed to, they speak the same language still more deci- 

 sively than those of Glarus in Switzerland. Of the 133 species enu- 

 merated and described by Agassiz, many are, it is true, peculiar and 

 unknown elsewhere, but as at Glarus there are genera, and in much 

 greater quantity, which, wholly unknown in any secondary rock, are 

 still living in our seas ; viz. Fistularia, Vomer, Torpedo, Lophius, Dio- 

 don, Rhombus, Clupeea and Anguilla. The presence alone of many 

 species of herrings and eels completes the proofs drawn from other 

 sources, that the deposits of Monte Bolca, like all the other num- 

 mulitic rocks of the Alps, must be completely severed from the chalk, 

 and be considered a true lower tertiary formation. 



Most geologists must, indeed, have been disposed to adopt this con- 

 clusion from the tabular arrangement of Agassiz, who, while the sub- 

 ject was still a matter of doubt, prudently placed the ichthyolites of 

 Monte Bolca, together with those of Monte Libanon, as a special 

 group between the cretaceous and tertiary deposits. I now, how- 

 ever, revert to the old opinion of Fortis, and definitively, I hope, 

 class the Bolca deposit as a true lower tertiary rock. 



I may terminate this portion of the memoir by saying, that when 

 we compare the Vicentine and Veronese eocene deposits with the 

 nummulitic rocks of the Savoy, Swiss and Bavarian Alps, we find 

 as much assimilation as can be expected to occur in deposits of the same 

 age, but of dissimilar composition, which lie at some distance from 

 each other, and have manifestly been separated by intervening lands. 

 In both, the true equivalents of the chalk are overlaid by limestones, 

 in which some of the sa^ne species of nummulites appear interstratified 

 with and overlaid by deposits in which are many of the same shells ; 

 whilst the most striking parallelism is marked by the abundant 

 echinoderms of the two regions — all quite distinct from those of the 

 preceding sera. In short, the deposits on the south as on the north 

 slopes of the Alps are proved, by their organic remains and superposi- 

 tion to rocks containing chalk fossils, to be of the lower tertiary age, 

 provided the groundwork of the classification previously adopted by 

 geologists be not entirely changed. 



In many natural sections, where the disruptions so frequent in this 

 chain have not interfered, the evidences are complete as to a former 

 continuous deposit from the surface of those strata in which any cre- 

 taceous fossils are discernible, through a vast series of strata in which 

 all the vestiges of life belong to a new sera. What then can these 

 nummulite deposits, whether in the Vicentine or in the Swiss Alps, 

 be, but true eocene ? If there be geologists who are not swayed by the 

 evidences of organic remains only, still they must surely be influenced 



