BASELEVEL, GRADE AND PENEPLAIN 109 
meanings of these words will depend much less on the preference 
of the older geologists and geographers of today than on that of 
their younger successors, I therefore urge those who are now 
taking up the use of such terms as baselevel and grade, denuda- 
tion and degradation, to consider carefully the meaning to be 
adopted for them. 
W.M. Davis. 
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