1896.] .^29 [Smith. 



fauna was, however, closely related to forms known in Europe and 

 Asia, but unlike those of the southern regions. Prof. AVilliams* after- 

 wards elaborated this theory and followed out closely the changes that 

 were inaugurated towards the close of the Devonian. The culmination 

 of these changes produced the Pacificf Carboniferous sea. 



The Carhoniferous Sea. 



From Chapter v, in Suess' AntUtz der Erde, Vol. ii, we get many 

 valuable suggestions as to the outlines of tlie Pacific Carboniferous 

 ocean. The Subcarbouiferous Avas the time of greatest transgression of 

 sea over the present land areas, while the sea in which the FusuUna 

 beds of Europe and America were formed was more circumscribed. 



The Waverly group when tra<;ed towards the west gradually takes on 

 the character of deep water fonnations ; it is persistent through Nevada 

 and California,:!: and has been shown hj the writer § to have a similar 

 fauna in these tw'o states. The Waverly probably persisted much 

 longer in the west than in the east, for in northern Missouri Dr. C. 

 R. Keyes|| has obseiwed that in the midst of an undoubted Burlington 

 fauna a well-marked Kinderhook or Waverly fauna reappears. This 

 lie explains by Barrande's theory of colonies. It is probablj^ an in- 

 cursion of the inhabitants of a deeper western sea, where the 

 Waverly had persisted longer, into the shallower eastern waters. The 

 work of the Geological Survey of Arkansas shows that a similar phe- 

 nomenon occurs in that state. The Fayetteville shale, which is of 

 Warsaw or St. Louis age, contains a fauna that differs markedly from 

 those of the limestones above and below it. A recent jjaper by Prof. 

 Henry S. WilliamsT[ shows the occurrence in the Fayetteville shale of 

 several species that occur in a doubtful U])per Devonian or Lower Car- 

 boniferous black shale in the White Pine district, Nevada. Along with 

 these Devonian or Waverly species occur others that belong much 

 higher, as Productus semireticulatus and Goniatites conf. sphwricus. 

 Below the Fayetteville shale is the Boone chert, which at the base con- 

 tains a decided Burlington fauna, and at the top probably belongs to 

 the Warsaw. This has been observed in so many places that there is no 

 possibility of mistake in the sequence of the strata. 



We have therefore in Arkansas an incursion similar to that in Mis 

 souri, except that in Arkansas the incursion came considerably later. 

 This is evidence that somewhere in the west the Waverly fauna per- 

 sisted throughout the Osage and possibly a part of the St. Louis. This 



* Proc. Amer. Assoc. Adv. ScL, 1892, Section E, Address, "The Scope of Paleoutology 

 and Its Value to Geologists." 



t See also Tschernischew, Man. Com. Geol. Rtissie,\o\. iii, No. 4, p. .364, on the physi- 

 •cal geographic changes that occurred in Europe towards the end of the Carboniferous. 



J Zoe, Vol. iii, p. 274, Proc. Calif. Acad. ScL, Oct. 17, 1892. 



^Journ. Geo/., Vol. ii. No. 6, Metamorphic Series of Shasta County, California. 



11 American Journal of Science, December, 1892, p. 447. 



•^ Amer. Journal qf Science. Vol. xlix, ls95, pp. 94-101. 



