218 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec. 13, 



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Val d'Astico resembled forms published by 

 Brander from the London clay of Hamp- 

 shire. M. Brongniart*, however, first sy- 

 stematically classified these strata as older 

 tertiary, and described their organic re- 

 mains, whilst our associate Dr. Buckland 

 arrived, about the same time, at a like con- 

 clusion in his general survey of the Alpsf. 

 But although there could be little doubt, 

 from the absence of cretaceous fossils, and 

 the presence of a multitude of genera having 

 a tertiary facies, that these shelly masses 

 were younger than the chalk, the great 

 desideratum still remained of natural exhi- 

 bitions of the true relations of these strata 

 to the inferior or secondary rocks. These 

 were the more called for, as some leading 

 geologists considered all the nummulite de- 

 posits of the Vicentine to be of cretaceous 

 age. In our rapid survey of parts of the 

 Vicentine in 1828, Sir C. Lyell and myself, 

 having visited the principal localities de- 

 scribed by Brongniart as '^ calcareo-trap- 

 peens," found these shelly deposits so com- 

 mingled with and interrupted by basaltic 

 .and other eruptive rocks, that we were 

 unable, any more than our precursor, to de- 

 tect an order of succession. It was after 

 my colleague had proceeded on his journey 

 to the south of Italy and Sicily, that in 

 returning to England across the Venetian 

 Alps, I obtained the desired proofs of that 

 order, in the clear and instructive natural 

 sections on the banks of the Brenta near 

 Bassano, and again between Possagno and 

 Asolo. I there saw the same nummulitic 

 and shelly beds as those of the adjacent 

 Vicentine, entirely free from igneous intru- 

 sions, reposing conformably on the scaglia 

 or the Italian equivalent of the chalk, and 

 passing upwards into strata of younger ter- 

 tiary age, the whole upraised in lines par- 

 allel to the direction of the Alpine chain. 



The figures of the remarkable sections 

 near Bassano were published in the ' Philo- 

 sophical Magazine,' but as that work is in 



* Memoire sur les Terrains de Sediment supe- 

 rieurs calcareo-trappeens du Vicentin, par Alex- 

 andre Brongniart, Paris, 1823. 



t See Annals of Philosophy, June 1821. 



