REVIEW OF OLD AND NEW STANDARDS OF PLEISTOCENE DIVISION 437 



by Eeid for nearly 100 kilometers on the east coast of Britain, from the 

 Flamborough Cape to the south of the Humber Estuary. The 33-meter 

 terrace of Scotland maintains a constant altitude and is regarded by 

 Deperet as a terminal phase of the Tyrrhenian shorelines. The marine 

 fauna (61 species) is that of the modern British seas, but with some 

 elements of a more temperate climate (Cytherea chione, Venus gallina) 

 and even of fresh-water shells of a warm climate (Corbicula fluminalis) 

 abundant near Kelsey and Croxton; the same species occur in deposits 

 of the 30-meter shoreline of Sussex, associated with a still more temperate 

 marine fauna. Similar 30-meter deposits are found at Speeton (near 

 Scarborough) below the "upper Boulder-clay." Xear Yarmouth, Nor- 

 folk, are "middle sands," intercalated between "upper" and 'dower 

 Boulder-clays," at a maximum altitude of 33 meters, containing (Wood 

 and Harmer) a fauna of eighty species, mostly British, partly Mediter- 

 ranean (Turritella incrassata, Lintopsis pygmaui, Cardita corbis, Cytherea 

 rudis), denoting a sea more temperate than the modern English seas. 



[= IV Glaciation, Mecklenburgian of Geikie J 



The final glacial phase in Great Britain is limited to certain Highland 

 massifs, the Hebrides, the Grampians, the Lake district, AY ales, and 

 Ireland. It is an epoch of great valley glaciers, often joined together at 

 their outlets on the plain. The strength and freshness of the terminal 

 moraines recall those of the Baltic moraines of the Mecklenburgian 

 glacier and of the Wiirmian moraines of the Alpine glacier. The original 

 attribution by Geikie of these local glaciers to a later time than the 33- 

 meter (100-foot) beach is confirmed by the observations of Wright ( L914.1, 

 page 368) on the western coasts of Scotland where the Loch Carron 

 glacier reaches the 20-meter shore. Similar levels in other parts of 

 northern Scotland convince Deperet that the local glaciation of the High- 

 lands corresponds to the 20-meter shoreline of his Monastirian Stage. 

 Traced around the Scottish coast, this 15-20-meter shoreline is compared 

 by Deperet with the Monastirian shoreline which he has recognized on 

 all the coasts of the English Channel, the Atlantic, and the Mediter- 

 ranean. [ Leverett is now of the opinion that Geikie's "Mecklenburgian" 

 does not include the earlier moraines of the last glaciation to the south 

 of (outside) the Baltic moraine. Penck as well as the Prussian geologists 

 think the Baltic moraine is not the limit of the last glaciation.] 



Post-Monastirian Stage. — After a marine recessive period, giving place 

 to the formation of peats and submerged forests, the sea advances again 

 and the last marine terrace of 25 feet, containing a modern marine fauna. 



