298 ANNUAL REPORT SMITHSONIAN INSTITUTION, 191*7. 



etc., with Elepkas pi*imi(/enius, etc. The plant remains indicate a 

 milder and more temperate climate than the present in that region. 



The greatest authority on the glacial period in central Russia is 

 N. Bogoljubow, who makes out the following succession in the Gov- 

 ernment of Moscow (39) . The remains of two glaciations are known, 

 the older one represented by traces of moraines, and by bowlder 

 sands and conglomerates, and the younger one by bowlder sand and 

 more perfect moraines. The interglacial period between these two 

 glaciations is divided by its deposits into three phases; first a "lake- 

 wood phase," of lacustrine marl and loam, next a " steppe phase," 

 of loess and loesslike sand loam, and finally a " wood phase." 



The flora of the interglacial was investigated by W. Sukatchev 

 (40), who finds indications that the climate was somewhat warmer 

 than the present. There is thus evidence for at least two glaciations 

 in central Russia, of which the first was the maximum. End 

 moraines attributed to this glaciation have been found by P. Tut- 

 kowski (41) in Wolhynia, associated with Asar; this agrees with 

 the limits of the first glaciation of eastern Germany, with which it is 

 correlated by most Russian geologists. Near Ovrutsch (42) he found 

 a mammal fauna in loess overlying bowlder sand, including Elephas 

 pHmigenius, Rh. ttchorMnus^ Orilms fossilk; this does not agree 

 well with the Rixdorf horizon of Germany, but appears to be older. 

 The succeeding glaciation, corresponding to the second in Germany, 

 did not reach so far south as Wolhynia. 



The center of distribution of these two ice sheets was in Finland, 

 and Sir R. Murchison (43) found erratics of igneous rocks, chiefly 

 granite, of Finnish types, 700 to 800 miles south of the parent rocks; 

 this was confirmed by T. Belt (44) who also noted that in pre- 

 glacial times the Russian rivers cut their beds much deeper than now. 



In the east of European Russia the limit of glaciation turned north, 

 along the Volga Valley and the Valley of the Petchora. In Fin- 

 land two glaciations were recognized by R. Sieger as early as 1892 

 (45) ; the lower one of these is represented by ground moraine, the 

 upper by a series of terminal moraines. Accompanying these are 

 two distinct systems of stria?, the younger crossing and abrading the 

 older as far as the terminal moraines, outside of which only the older 

 system remains. The older stria? extend from the center of distribu- 

 tion in a uniformly radial direction, while the younger are affected 

 by local irregularities of contour which the ice sheet producing the 

 former was thick enough to override. In the southeast the limit of 

 the younger moraines is Hango Head in the Gulf of Finland. The 

 deposits in the lower course of the northern Dwina were investigated 

 by Wollossowitsch (46). From two borings in Archangel he de- 

 scribes the following general section : 



