THE BASIN PROVINCE 145 



"It would seem that the general physical conditions prevailing throughout 

 the world at the beginning of and during Permian time must be taken into account 

 in making broad correlations of Carboniferous and Permian faunas. The sig- 

 nificance of the evolution of a provincial fauna in a great epicontinental sea, 

 covering 200,000 or 300,000 square miles, with inadequate and perhaps only 

 intermittent connection with the open sea of the continental shelves in America, 

 should be as great as the evolution of a fauna in the Uralian region. This sig- 

 nificance is increased when it is taken into consideration that both developed 

 during the time when the water was being drawn from the shelves of both con- 

 tinents and the areas of the inland seas were being greatly reduced. 



" In this light the parallelism in the nature of the deposits of the two regions, 

 accompanied by a like parallelism of faunal changes, is of fundamental impor- 

 tance, and deserves a larger consideration than Dr. Girty has given it. For 

 instance, the introduction of new faunal elements, the sudden and nearly com- 

 plete disappearance of the Fusulina, and the occurrence of Schwagerina bear the 

 same relations to the early gypsum deposits and the development of the Red 

 Beds, in the Kansas section, as they do in the eastern part of European Russia. 

 If I read the stratigraphic account of the Guadalupes aright, it seems that the 

 general considerations of the later Permian apply to them likewise. The un- 

 conformity, if such it be, carrying away the Capitan limestone from the flanks 

 of the mountain of which it forms the top, and over the unconformity the deposi- 

 tion of the Castile gypsum, Rustler formation, and Red Beds, strongly suggest 

 that the Guadalupe region was similarly affected with the region to the north- 

 ward so far as a general Permian emergence is concerned. In this light the 

 Guadalupian faunas must be largely contemporaneous with the Permian faunas 

 of America and Eurasia. In the eyes of the reviewer, judging from figures and 

 descriptions only, there is where their faunal relationships would also place them. 



"The point is made that the faunas are so different that, if they are contem- 

 poraneous with those of the Mississippi Valley of which Dr. Girty seems to be 

 doubtful they could not both be covered by a single general term (like Permian?) 

 for their designation. That they are quite distinct from anything yet brought 

 to light on the continent will be granted at once by anyone familiar with the 

 subject. The one is a cosmopolitan, open-sea, coastal-shelf fauna, while the 

 other is a more isolated epicontinental sea fauna rather thoroughly separated 

 from its neighbor on the south and perhaps belonging to a different climatic 

 zone. Should they prove to be equivalent in time, I see no reason why they 

 might not be covered by a single term of ordinal rank, their local geologic designa- 

 tions being sufficient to differentiate them. 



"That it was impossible for the Guadalupian and Mississippi Valley clear- 

 water faunas to intermingle to a considerable extent after the time represented 

 approximately by the Topeka limestone, unless by a circuitous route, no one 

 acquainted with the geology of the intervening region would hesitate to state." 



Beede's explanation of the impossibility of the intermingling of the 

 waters of western Oklahoma which were already depositing red beds and 

 the clear waters of the sea which deposited the Capitan limestone are 

 quoted on page 100. To the author there is considerable difficulty in 

 accepting either of these explanations. 



The red beds of the Pecos Valley are in all probability of equal age with, 



and the same in stratigraphic position as, the uppermost red beds of southern 

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