In Carboniferous and Permian Epochs 163 



flora and fauna we have already been studying. A sug- 

 gestive discussion of some of these problems may be found 

 in Chamberlin-Salisbury's "Geology" (5:11:640-677). 



With increasing firming, but also faulting of the earth's 

 crust, active volcanic and seismic disturbances gave rise to 

 huge masses of volcanic rock, that not only added to, 

 hardened, and deformed the older strata, but in known in- 

 stances aided powerfully in elevating mountain masses, as 

 has been shown for the Appalachian and Ouachita ranges 

 in the United States. But in this process much of the 

 former relatively flat marshy ground of the Carboniferous 

 seems to have been elevated and converted into wide pla- 

 teaux, much resembling those of Thibet, and the "bad 

 lands" of the West. These then became subject to periods 

 of desiccation, and alternately of rapid denudation, by ac- 

 tion of rains descending from the mountains. 



As gradually elucidated in Europe during the past 

 seventy-five years by King (//j), by H. B. Geinitz (//<5), 

 by Weiss, {iij), by Goeppert {118), and specially by 

 Fritsch {iig)^ as traced in India by Medlicott and Blan- 

 ford, also by Oldham (720:191), and in North America 

 by Fontaine- White {121)] by Prosser {122), by Hussa- 

 kof and Case {12^), the formation exhibits considerable 

 diversity of character, "that seems largely dependent on 

 whether the strata were: (a) deposited in a marine hab- 

 itat; (b) deposited in rather deep lacustrine areas as shaly, 

 sandy, or gravelly strata; or (c) formed in estuaries, 

 swamps, lagoons, alluvial plains, and open or covered 

 woodlands" (725:207:101). These by no means follow 

 definite and successive relations, but except for the last — 

 which is best developed near the top of the system — the 

 marine and lacustrine are often interbedded. The marine 

 rocks, usually limestone in nature, attain their greatest de- 

 velopment from the Alps eastward to North India, and in 

 the western and south western United States. These con- 

 tain a rather poor assemblage of typical invertebrate ma- 

 rine forms, but mixed amongst these are no vertebrate 

 remains. 



