156 OSCAR H. HERS HEY 



peneplain. Below the level of the peneplain he has found vari- 

 ous remnants of a series of sandstones and gravels, the age of 

 nearly all of which, on the basis of abundant paleontological evi- 

 dence, is placed late in the Miocene period. Some of these 

 sandstone areas were uplifted, deformed, and planed off by stream 

 erosion, producing a peneplain (the Bellspring) , which is prac- 

 tically continuous with the Klamath peneplain developed on the 

 older rocks, making it apparent that the latter was not materially 

 disturbed until long after the deposition of these supposed late 

 Miocene sediments. 



Then the country was uplifted to the amount of 500 feet near 

 the coast, but increasing inland, and there was locally developed 

 a lower peneplain,''which Mr. Diller has named the Sherwood. I 

 am unable positively to identify the late Neocene grade level 

 which I have observed in the Trinity basin with either of Mr. 

 Diller's two main pleneplain levels, as there has apparently been 

 an unusual deformation in the vicinity of the south fork of Trin- 

 ity river, and I am not sufficiently acquainted with that region 

 to give it its true value. The reader is referred to the map 

 accompanying Mr. Diller's paper for the geography of the terri- 

 tory herein discussed. 



The few short sections of late Neocene river channels which 

 are known in the southern portion of the Klamath region are 

 evidently mere remnants of an extensive system which must have 

 been developed over the entire territory — a system comparable 

 with the Neocene channels of the Sierra Nevada region. In the 

 latter province there was an uplift without much deformation 

 other than a gentle westward tilting. In the Klamath region, on 

 the contrary, the differential uplifting took the form of broad 

 arches. This may be likened to the arching of the Coast Range 

 region to which is due the present parallel ranges separated by 

 broad valleys, both northward and southward from the Bay of 

 San Francisco. In fact, the arching of the Klamath region was 

 part of the Coast Range system of late Tertiary and early Qua- 

 ternary mountain-building. But in the Klamath province the 

 entire territory was so greatly uplifted that the streams have 

 trenched deeply beneath the troughs as well as into the arches, 



