208 G. F. BECKER EARLY CRETACEOUS OF CALIFORNIA. 



Dr. C. A. White : The paleontological discoveries which Dr. Becker has 

 made in southern Oregon prove conclusively, what had before been rendered 

 probable by the labors of Dr. Dawson and Mr. Whiteaves in British Colum- 

 bia, that there is'really a commingling of the fossil faunas of the Knoxville 

 and Horsetown divisions of the great series of strata to which the term 

 "Shasta group " has been applied in California, and that those strata all 

 belong to one great paleontological horizon. Dr. Becker's well-known con- 

 tributions to our knowledge of the geological history of the Pacific Border 

 region are of prime importance, even if the assumed geological age of the 

 formations to which he has referred should not prove to be demonstrable. 

 Upon this latter point I have now much doubt, although his quotations of 

 my views, at the time I expressed them, are in the main correct. For ex- 

 ample, I do not now think that we are warranted in even approximately 

 correlating any of the Cretaceous deposits of the Pacific border region with 

 any one of the subdivisions of the European Cretaceous. We certainly are 

 not 3^et able to satisfactorily correlate any of them with any of the forma- 

 tions of the interior and eastern portions of this continent. Again, while I 

 have never published any opinion concerning the reputed Triassic fossils 

 obtained from the Mineral King district, I am not now disposed to deny that 

 the strata from which they came may represent a part of the European 

 Triassic. At the time I examined them at Dr. Becker's request I believed 

 he would be warranted in regarding them of Triassic age. They consisted 

 of a number of molluscan generic forms such as in p^rt characterize the 

 European Triassic, and among them was one Paleozoic form, namely, a 

 Spirifer. I did not then realize fully as I now do the importance of extreme 

 caution in pronouncing upon such questions as that collection presented. 

 I had not then made the discovery of Mesozoic forms in the Permian of 

 Texas, the results of which are soon to be published ; Gemmellaro had 

 not then published the remarkable commingling of both molluscan and 

 crustacean Mesozoic types which he has discovered in Sicily ; and Karpinsky 

 had not published his important similar discoveries in Russia. It is true 

 that I knew of a part of Waagen's related discoveries in India, but I was 

 then more disposed than now to follow the general custom of regarding such 

 a state of things as exceptional rather than as one to be looked for in any 

 part of the world, especially upon the confines of geological systems. Still, 

 all this does not impair the value and correctness of Dr. Becker's conclu- 

 sions as to the time of the great upheaval to which he alludes with reference 

 to that of the deposition of the latest formation directly involved in it. 



gradual transition into metamorphic rocks, and upward they are succeeded, just as in California, 

 by seemingly conformable shales 9nd sandstones containing Horsetown fossils intermingled with 

 Aucella. Mr. Will. Q Brown, who has given much attention to the geology of Douglas county, dis- 

 covered Aucella in that region and called my attention to it in 1888, when we first examined the 

 region together. The limestone in which the discovery was macie may be of nearly the same 

 horizon as the one three miles west of Paskenia, where Aucella occurs in abundance. 



