forming thcSouthern Flcmk ofthcTyrolcse Alps near Rasscmo. 409 



to accuinulate on its surface ; — On the contrary, we here find a 

 continuity of marine deposits or conformable passage from the 

 rocks called tertiary to those named secondary', the only 

 grounds of distinction between the two consisting in the difiTcr- 

 ent nature of their organic remains. 



It has been mentioned, that to the west of the district 

 described, volcanic rocks are intermingled with the regular 

 deposits. I only made a short excursion in that direction, and 

 near St. Agata and Florian I observed tertiary rocks tra- 

 versed by amygdaloidal trap and the vitreous basalt of Monte 

 Gloso. These and the contiguous regions further westvvaid 

 are fully described by Fortis and Maraschini, both of whom 

 show that ifrneous rocks have there burst throun;h and alter- 

 nated with deposits of different ages. By these numerous 

 vents we may therefore presume, that the expansive forces 

 were finally elaborated, which when confined below may have 

 elevated the neighbouring deposits, I have therefore selected 

 these de}iosits as types of observation, because they are wholly 

 exempt from the confusion usually incident to any intermix- 

 ture with volcanic rocks. 



List of Organic Remains observed in a cursorij Examination of 

 the Tertiary Deposits near Asolo, Possagno, Bassano, S^r. 



(Named by Mr. James de C. Sowerby.) Localities in other Parts 



B[ VALVES. of Europe. 



Ostrea. Several species, all in the")^ 



younger beds above the blue marl j 



Pectcn pleitronectes and other species ; ^ o i 



, .-' n • ,1 11 I- f Subapennmes 



cnieriy m the upper sands subordi- V ^i { . t,^ i 



, { ,, ' ' 1 ^ i throughout JtaJv. 



nate to the conglomerates ) ° 



Chama squamosa. Min. Con, Interme-1 -r, ^ i-rn tt ^ 

 -' 1-^11 1 y Barton cliir, Hants, 



diate blue marls, j 



Lucina conccntrica, \^am. In the hin-her 1 ^ii .• a ,• o 



X ^ c\\ 1 /• I lacentia, Asti, i\c, 



beds oi blue marl, J 



mutabilis, Deshayes, do, do, Grignon. 



Univalves 

 (chiefly in the middle and lower bhie marls). 

 Rostcllaria sinuosa? ]>ourdeau\. 



Cas5?s <//«</fw?ff (of Grateloup& Basterot.) > ' i .. ' 



Conns stromhoides {concinnns of Sower.) \ Ilighgati', Bnilon, 

 (See Min. Conch, t. 302. f. 2.) j and Paris. 



C Lowest beds of 



Ftisus longccvns. Min. Couch, t. fJ.'J < Calcaire grossior, 



(^ Lonilon clay, i^cc. 

 jV. .S. \'ol. r,. No, .'JO. .Jiuic l«2r». ;5 (! M'rlauia 



