Lawson.] 



Coast of Northern California. 



259 



diastrophisrn, since, as in the case of the Eel River as compared 

 with the rivers to the south of it, the stages of degradation may be 

 so different as to suggest differential movements of adjoining regions, 

 where none may have taken place. In view of these considerations 

 it seems to the writer that, while the terminology which has been 

 developed largely by Davis' writings is philosophical and admira- 

 ble as far as it goes, it is yet defective in practically ignoring the 

 important factor of relative susceptibility to degradation. In offer- 

 ing this criticism the writer does not shut his eyes to the difficulties 

 that stand in the way of recognizing this factor in geomorphic 

 terminology; and it may be possible that a simple nomenclature, 

 defective to the extent indicated, will be found preferable to a more 

 comprehensive but more cumbersome one. If, however, numerical 

 formulae be used to express the geomorphy with reference to the 

 position in a graded scale, as recently suggested by Davis,* the 

 factor might be introduced. Thus, it seems to the writer that if 

 there are two portions of the same original block or constructional 

 form which, in the same interval of time and for the same attitude 

 of the land, have advanced differentially in the geomorphic cycle, 

 the formulae might be improved by introducing a factor for the rate 

 of degradation. This factor would also indirectly express the char- 

 acter of the topography to a certain extent; for a rapid rate of deg- 

 radation would indicate a soft terrane, and this would probably in 

 general be found to involve a greater multiplicity of drainage lines 

 and so a more choppy character of relief. 



The Scotia Section. — The strata so well exposed in the Ferndale 

 section may be followed along their strike to the vicinity of Scotia, 

 and they doubtless extend for a considerable distance beyond this 

 point, although they were not followed farther in this direction by 

 the writer. Towards Scotia the beds become more arenaceous, 

 grayer in color, more fossiliferous, and structurally they are inclined 

 at much higher angles than in the Ferndale section. The more 

 arenaceous character of the beds and the greater abundance of 

 fossils, for the most part in an excellent state of preservation, indi- 

 cate an approach to the shore line of the basin of deposition. On 



* Journal of Geology, Vol. II, No. 1. 



