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Show fiU ERA OF THE CARBONIFEROUS FORl\IA'.rlON. would gather in every sea, near the mouths of great riveua On the exhaustion of the superabundance of carbonic acid gas, the coal formation ·would cease, ~nd the earth !!light again become a suitable theatre of b~1ng for land an_1mal~. The termination of the carboniferous formahon IS marked by symptoms of volcanic violence, which some geologists have considere~ to. denote the close of one system 0f things and the begtnning of another. Coal beds generally lie in basins, as if following the curve of the bottom of seas. But there is no such basin which is not broken up into pieces, some of which have been tossed ur on edge, others allowed to sink, causing the ends of strata to be in some instances many yards, and in a few several hundred feet, removed from the corresponding ends of neighboring fragrnents. These are h~ld to be :res~lts oi volcanic movements below, the operatlon of whiCh 1s further seen in numerous up bursts and intrusions of volcanic rock, (trap.) That ti:ese disturbances t~ok place. about the close of the formation, and not later, IS show~ In the fact of the next higher group of strata being comparatively undisturbed. Other symptoms of this time of violence are seen in the beds of conglomerate which occur amongst the first strata above the coal. These, as usual, consist of fragments of the elder rock, more or less worn from beincr tumbled about in agitated water, and. laid down in a m~d paste, afterwards hardened. Volcanic disturbances break up the rocks ; the pieces are worn in seas ; and a deposit of cono·lomerate is the consequence. Of por; phyry, there are 0some such pieces in the conglomerate of Devonshire, three or four tons in weight. It is to be adn1itted for strict truth, that, in some -parts of Enrope, ~he carboniferous formation is followed by superior deposits, without the appearanoe of snch di::;turb~nces between their respective periods; but apparet:tly this case b_elongs to the class of exceptions already noticed.* That d~sturbance was general, is supported by the further anc~ nnp_ortant fact of the destruction of many forrns of organic b~mg previously flourishing, particularly of the vegetable lnng-d0m. ~"Some ofthe most considerable di slocations of the border of the coal fields of Coal brookdale and Dudley, happened after the depo· sHion of a part of the new red sandstone; but it is certain that those of Somersetshirc and ,-loucestcrshire were completed l>efore tl18 date of that rock. ''-Philips ERA OF THE NEW RED SANDSTONE rERRESTRIAL ~OOLOGY COMMENCES WITH REPTILE!!. F1:RST TRACES O:F BIRDS. THE next volume of the rock series refers to an era distinguished by an event of no less importance than the commencement of land animals. The l\lew Red Sandstone Sy~tem. is subdivided into groups, some of which are w~nbng 1n some places; they are pretty fully developed In the north of En0o-land in the followino- a~·cendin(J' d ' ::") 0 or er: 1. Low~r red sandstone; 2. Magnesian lime tone; 3. Red and white sandstones and conglomerate; 4. Variegated marls. Between the third and fourth there i , in Germa~y, ano~her group, called the Muschelkalk, a word expressing a hmestone full of shells. The first group, containing the conglomerates already adv~rtcd to, seems to have been produced during the time of d:sturbance which. occurred so generally after the carb~ migenous e:a. T~Is new era is distinguised by a pauCity of organic rema1~s, as might partly be expected from ~he appearances o~ dtsturbance, and the red tint of the 10~ks, the latter being communicated by a solution of oxide of Iron, a substance unfavorable to animal life. The .secon~l group is a limestone with an infusion of m~gnes1a. It Is d~veloped !ess generally than some other , but occurs conspicuously In England and Gennany Its P~~ce, above the red sandsto~e, shows the recurre~ce of ~u c~m~tances favorable to animal life, and we accordincrly nd In 1t uot only. ~oophytes, conchifera, and a fe\v tribes 0~ ~s~, ~ut some faint traces .of land plants, and a new and ~t~r ~hnn a~pearance-a rept~le _of saurian (lizard) charac~!, ar:alogous. to the now ex1sbng family called monitors. b e~.ains of tlus creature ar'; f0und in cupriferous (copperrJ:~~~ gl slate connected wtt~ the mountain limestone, at t· e d ~nd Glucksbrun, 1n Germany, which rna be tJ~~~~ as eVIde1~ce that dry land existed in that a"e ~ear bl pl~es. fhe magnesia hmestone is also remarka nr~das e last l'~)?k in which appears the leptrena 0; ~on u~ta. a conch1ier of r:umerous species which mak~s a . ~ptrcuous appearance In a] l previous sea::s Tt I·s li"I wr:;e o be b, . d 1 , · .1 (e- o. serve ' t lat tne fishes of this ao-c to th genera of wluch the namos palreoni..:cus C' t to ' l e .... o , a op erus, p a- |