286 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [DeC. 13, 



the coarse conglomerates have entirely disappeared, and are suc- 

 ceeded by sand, marlstone and marl (?'), in which are forms of 

 Cerithium, Cardium, Yermetus, &c. These are followed by sand- 

 stone (j) and impure calcareous concretions, which as you approach 

 Castel ^lontalto alternate wdth finely laminated shale. In all this 

 space (not less than two English miles), the strata dip at 20° to 25° 

 to the south, and certain subapennine shells occur, such as the 

 Lucina Asfensis (a well-known species of the hills of Asti, which 

 we found near Bardassan), associated with the Cleodora ohtiisa and 

 Ringicula Bonelli of the Superga ; thus already proving an inter- 

 mixture of species which authors may cite, some as miocene, others 

 as pliocene. 



Pursuing the ascending section, and leaving behind all the true 

 miocene sandstones, we come into marls, shale and marlstone, often 

 white, which are overlaid by other marls descending under the yellow 

 sands of Chieri. These last-mentioned marls {k), which are usually 

 considered subapennine and are covered by sands (/), charged with 

 the youngest known shells of the group, contain the following species, 

 as named for me by Dr. E. Sismonda : — 



Turbinolia duodeciracostata, Gold/., P. 

 Terebratula DeBuchi, Mich., M. 

 Ostrea cochlear, Poli, P.M. 

 Pecten cristatus, Bronn, P. 

 Nucula concava, Bronn. 



interrupta, Nyst. 



Nicobarica, Lk., P. 



placentina, Lk., P.M. 



rostrata, Lk. 

 Limopsis aurita, Sassi, M. 

 Area diluvii, Lk., M. 

 Lucina Astensis, Bon., M. 



spuria, Desk., P.M. 



transversa, Bronn, P. 

 Venus alternans, E. Sismd., P. 

 Erycina coraplanata, Red. 

 Hornia seminulum, Phil. 

 Dentalium circinnatum. Sow. 



coarctatum, Lk., M. 



fossile, Linn., M. 



inaequale, Bronn, M, 



pseudo-entalis, Lk., M. 



rectum, Linn., M. 



sexangulare, Lk., M. 

 Cerithium vulgatum, Brug., P.M. 



inflatura. Bell., M. 

 Nassa costulata, Ren., M. 



semistriata, Br., P. 



seiTata, Br., P. 

 Buccinum polygonum, Br., P.M. 

 Cassidaria echinophora, Lk., P.M. 

 Cassis texta, Bronn, P.M. 



variabilis, Bell, et Mich., M. 

 Cancellaria Bonelli, Bell., M. 



calcarata, Br. 



lyrata, Br., M. 



mitrasformis, Br. 



Cancellaria varicosa, Br., P.M. 

 Pleurotoma brevirostris, M. 



cataphracta, Br., M. 



Coquandi, Bell. 



denticula. Bast., M. 



dimidiata, Br., M. 



intermedia, Bronn, M. 



intorta, Br., M. 



monilis, Br., M. 



obtusangula, Br., M. 



rotata, Br., P.M. 



turricula, Br., P.M. 



turritelloides. Bell. 



Rochettae, Bell. 

 Raphitoma harpula. Bell., M. 



pHcatella, Bell, M. 



vulpecula. Bell., P.M. 



column ae, Bell. 



textilis, Bell., M. 

 Ficula ficoides, E. Sismd. 

 Fusus aduncus, Bronn, M. 



angulosus, E. Sismd., P.M. 



crispus, Bors., M. 

 , lamellosus, Bors., M. 

 i longiroster, Br., M. 

 /• raitrsefonuis, Br., M. 

 Triton Apenninicum, Bronn, M. 

 -Ranella marginata. Sow., P.M. 



reticularis, E. Sismd., P.M. 

 Murex craticulatus, Br., P. 



funiculosus, Bors. 



fusulus, Br., M. 



Lassaignei, Grat., M. 



polymorphus, Br., P.M. 



spinicosta, Bronn, M. 

 Typhis fistulosus, Mich., M. 

 Columbella nassoides. Bell, M. 



