424 



PROCEEDINGS OF THE ACADEMY OF 



[1897. 



shut in a narrow bed with rocky banks that often assume the aspect 

 of a veritable gorge of 40 m. (131 ft.) and more in height. 



The country, which appears ordinarily flat, falls away only in the 

 neighborhood of the rivers, where it is broken abruptly into rocky 

 escarpments. The courses of the streams thus display scenery en- 

 tirely different from the surrounding country. Their lower courses 

 are said to be distinguished by large, flat, marshy valleys bounded 



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Upper Cocir&e, 



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O 1_ 



v > 





1 — I 



o *- 



^3 > 

 «.. _ 



Middle Coarse 

 •xjV 



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I 



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Lower Course 



( jrorm Livref Qaide "VTf>f>. 5<$r<s>) 



Fig. 2. 



by terraces ordinarily rounded and sometimes cut by ravines. 

 The river meandering in this valley and approaching sometimes 

 one and sometimes the other of these terraces, cuts escarpments more 

 or less deep, sometimes vertical, permitting a view of the tertiary 

 rocks and alluvial deposits. Here and there one sees the remains 

 of old river beds called "staritsa." 



