ON thp: movements of the earth's crust. i]bd 



« 



clay were deposited, in all with twenty or more alternations (according 

 to Lepsius, Das Mainzerhecl;en). All these deposits are Miocene. 



We now pass further forward in time. The Pliocene has four oscilla- 

 tions, 13', 14', 15', and 16'. We have already mentioned the Congeria- 

 beds of the Vienna basin. In England there are three oscillations : 

 Coralline Crag (14'), Red Crag (15'), and Cromer Clay or Westletou 

 Shingle (16').' Profiles of these are to be found in Quart. Journ. Geol. 

 Soe. Lo7id., 1871 (by J'restwich). The climate of Europe began to become 

 colder in the Pliocene. Even the oldest deposit in the Pliocene of En- 

 gland contains stones which may have been grooved by ice, and at the 

 close of the Pliocene there were already great glaciers ; the Pliocene was 

 followed by the Glacial epoch. We have seen how, during strong and 

 extensive volcanic action, previously marine basins were during Oligo- 

 cene, and especially Miocene, times uplitted above the sea not to be 

 depressed afterwards (Paris, Vienna, Hungary, the Mayence basin, and 

 we may add Switzerland), and we have seen that the Alps were up- 

 heaved in Miocene times. The Faroes and Iceland were built up, at 

 any rate in great part, at the same time by basalts and lavas; perhaps, 

 moreover, the submarine bank which connects Europe with Greenland 

 was uplifted during the last portion of the Miocene period. In the Medi- 

 terranean, according to Neumayr(see Suess. Antlifz der Erde, i. p., 425) 

 the coast-lines at the close of the Pliocene lay even lower than at the 

 present day. No doubt all these elevations have had much influence 

 upon climate. Changes in the length of the day are dependent upon 

 variations of the eccentricity. Geographical changes follow ui)on the 

 increase of the day, and climate changes with the distribution of land 

 and sea. 



The Coralline Crag in England (according to Prestwich) has a thick- 

 ness of only 25 meters, and can not have many alternations. After this 

 stage was formed the land rose, but was again partially depressed under 

 the sea. During this depression was formed the Red Crag, with the 

 Chillesford Clay. In the Coralline Crag two shore-lines were hollowed 

 out one over the other and the new stage lies now on the old shore plat- 

 forms. The Red Crag is thinner than the Coralline Crag and can not 

 include many alternations. 



In Belgium, also, we have two Pliocene stages, which correspond to the 

 two English Crag-stages : the Scaldisien, stages superieur et inferieur. 

 To these two oscillations of the North Sea correspond two contempo 

 laneous ones of the Mediterranean. Suess calls them the third and 

 fourth Mediterranean stages. And even in the earliest part of the Pli- 

 ocene the Mediterranean fauna indicates a somewhat colder climate 

 (Suess, /. c. I. p. 431). 



Italy possesses thick Pliocene formations. Seguenza describes de- 

 posits 500 to 600 meters in thickness from this i)eriod, I have been 

 unable to obtain profiles of these deposits. They arc in part conglotn- 

 erates and shore formations, like the great Miocene Mollasse of Switz- 



