appendix: review and critique 475 



hypothesis that excludes dias trophism. It would seem that it must be 

 apparent 'to any one at all familiar with the subject that it is necessary 

 to bring in diastrophism to account for the fluctuations of the sealevel. 



(5) Leverett considers that the correlation both of the Tyrrhenian 

 and Sicilian stages of Deperet is too loose. For example, Deperet in- 

 cludes within the Tyrrhenian the temperate fauna of an interglacial 

 stage which precedes the Polonian-Eissian glaciation; he allows a stage 

 of glaciation also to fall within the Tyrrhenian ; furthermore, lie refers 

 the cold Postglacial fauna to a terminal phase of the Tyrrhenian. He 

 thus takes no account of a possible lowering of the sealevel (eustatie 

 movement) in the glacial stage by the abstraction of water to form the 

 ice-sheet, but from the presence of a 33-meter beach on top of the glacial 

 deposits, as well as of a beach of 33 meters beneath the glacial deposits, 

 he takes the altitude of 33 meters as a basis for correlating both inter- 

 glacial and glacial stages with a stage of the Mediterranean Sea of 33 

 meters. 



(5a) Similar laxity is shown in Deperet' s attempt to carry the Sicilian 

 correlation of 90-100 meters into the glaciated districts around the 

 Baltic and North seas. The Sicilian is thus made to correlate with the 

 Scanian; also with an interglacial stage between the Scanian and the 

 Saxonian. Against this correlation is the fact that the sea was actually 

 low in the Baltic basin in the interglacial stage between the Scanian and 

 the Saxonian. [The sea was low for only a portion of the stage; see 

 final correlation chart by Osborn and Beeds, figure 13.] The interglacial 

 Paludina fresh-water beds at Berlin lie 40 meters below the present 

 streamlevel. These Paludina beds were considered by Wahnschaffe 

 (1909.1, pages 324, 325) as among the best instances in Germany of a 

 warm interglacial fauna between the first and second drift sheets, namely, 

 in First Interglacial time. These Paludina beds can be positively referred 

 to the First Interglacial stage in question and definitely disprove 

 Deperet's idea of a high-water sealevel in First Interglacial time. 

 WahnschafTe finds no evidence of disturbance and subsequent marine 

 transgression in the Paludina beds; his work is the fullest and best 

 general discussion of the "drift" of Germany that has been written. 



(6) To sum up: (1) Leverett considers that Deperet' s papers repre- 

 sent a zealous presentation of a theory which Deperet had conceived and 

 regarded as new — a theory, however, which has not been overlooked by 

 those who have devoted their lives to glacial and fluvial investigations ; 

 in other words, Deperet has been led to depend too much on coincidences 

 in altitude of terraces and on the questionable assumption of very ex- 

 tensive eustatie movements. (2) The correlation paper of Brooks gives 



XXXII — Bull. Geol. Soc. Am., Vol. 33, 1921 



