28 GEOLOGICAL MEMOIRS. 



Castelliiii collection, now forming part of the Museum of Natural 

 History in the University of Padua. [T. D.] 



On Post-tertiary Shells /rowz the Coast o/" Greece. 



By Dr. M. Hoernes. 



[Proceed. Imp, Geol, Instit. Vienna, January 29, 1856.] 



Dr. Hoernes communicated a list of 87 species of marine molluscs, 

 found subfossil near Kalamaki, on the Isthmus of Corinth, and 

 lately sent to the Imperial Museum by M. Th. de Heldreich, Director 

 of the Royal Botanical Garden at Athens. The specimens were 

 found between Kalamaki and Lutraki, at a height of from 30 to 60 

 feet above the present high -water-mark, imbedded in a mass of 

 shell-fragments, with small rolled pebbles of serpentine and reddish 

 quartz, altogether forming a calcareous sandstone. All the species 

 are still living in the neighbouring sea. 



Similar deposits are known to exist along nearly the whole coast 

 of the Mediterranean, — in the Morea, in Rhodes, Cyprus, Sicily, 

 Italy (Puzzuoli), Algeria, Spain, &c. Hence it may be concluded 

 that at an earlier epoch the countries surrounding the Mediter- 

 ranean have undergone an upheaval, which, as careful investigations 

 seem to prove, has affected the continents of Europe, Asia, and 

 Africa bodily ; so that at the epoch known under the name of 

 "Neogene" (Pliocene and Miocene of Lyell), the Atlantic Ocean 

 and the Mediterranean may have extended considerably further than 

 they do now. In the south and south-west of France, in the May- 

 ence and Upper Danube basin, in the basins of Vienna and Hungary, 

 in the plains of Germany, a great portion of Russia, the whole extent 

 of the valley of the Po, and elsewhere, there exist evidences of the 

 waters having covered all these areas. At the same epoch the 

 Caspian Sea was still in immediate connexion with the Euxine, and 

 Africa was an island, the borings undertaken by the Canal-com- 

 mission having shown that the Isthmus of Suez is for the most part 

 composed of deposits abounding in Neogene fossils. Similar fossils 

 have been found in Algeria and in Oran, so that the whole of North 

 Africa, together with the Sahara, may be reasonably supposed to 

 have formed part of the Neogene sea. 



It also appears that the upheaval was extremely slow, all the 

 neogene fauna of Europe exhibitmg gradual passages from an extinct 

 fauna to one perfectly agreeing with that of the present Mediter- 

 ranean fauna. The species of the lowest neogene strata have a sub- 

 tropical character ; those of later date indicate a climate more and 

 more approaching to that existing at present ; and of the S7 species 

 from Kalamaki, fifty are identical -with forms from the Vienna basin. 



From the sinking of the relative level of the sea, as an effect of 

 the upheaval, and the influx of fresh water into limited basins, the 

 true marine species died out and gave room to a new fauna peculiar 

 to brackish water (the Cerithian strata) ; just as changes are now 

 taking place on the shores of the Caspian. At last even these 

 species could no longer exist with the gradually diminishing water- 

 level, and made room for the comparatively few moUuscan forms at 

 present inhabiting our dry lands and fresh waters. [Count M.] 



