578 WILLARD D. JOHNSON 



necessary above-sea surface for snow accumulation. The degrada- 

 tion limit would be determined by the lifting power of the sea. 



The hypothesis, at this stage, is of much less importance than 

 recognition of the anomalies of fact, of which it offers a tentative, 

 even venturesome, explanation. In the fiorded regions of the globe, 

 notably in the Patagonian Andes, of which a well- controlled recon- 

 naissance survey has recently been completed, we have examples 

 not only of fiords deepening backward for many miles into rising 

 grades, but of fiord lakes, in parallel series, penetrating from foot- 

 hills on the one side to foothills on the other, transecting a range. 

 In explanation of such deep channels, whether occupied by arms of 

 the sea, by lakes, or by feebly moving streams on meander bottoms, 

 the appeal to grades, it seems to me, will be most cogent. 



WiLLARD D. Johnson. 



Washington, D. C. 



