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Show [ 174 J bed of sandsto11c. l3olow the ht'u conL.tiuino· the {erus, tltcrc arc threod, tittct beds o( coal, each cp·uatt'd by about 5 feet of clay. Before" .'~· · 1 ,. · · · 1 - ,.xatnut mgt le 00 lllc.spcCHOCllS jllSl lllelltlOlle<., 1 COnlparcd these fo~~il ferns Wi 1 · a large eollectlon from tho coal tllea~;urc of Penn .. ylvania n11d Oh 'to dt.1 was qul· le ev1·c l e~H t lw .t t I1 1· ~ J'o rmatt· on con 1c1 not be of the ~anw age. ' Tahn er ll arc several spectmcns wh tell I can 0111 y rc~~r to the Glo~ ·opteri~ Pltt'll' .. e .1 · · ) 1· · r .1 (sec ucscnptwn, an oo 1t1c l · 1 . tpsu H) 'SI · aw tlu. a one, w1th the '"Cilt'l"tl ell ' . . h · • arac. tor of the other ~peclCs. attd tile n.bsence of the ln.rn·e stCllt'4 s•) c'ortlm · • ., J on m tit<.' coal penocl, bad led 1nc to refer t!J,~m to tit' oolitic period. 1 couc · llowevc•r that we have ~eu~·cely snflicient cvicleucc! to jnsf ify tit is referee~~:~ an~ though a.moug till~ fossil shc_ll' there arc ttone ~lccidcdly typi1~al of th~ oolJil', yet u.c1ther arc ~II<'Y so t~l n11y ot.IH~t· formatt.ott; and t!w litholoO'ical character of the n1ass Js 11ol relw.bln evtJence. Sttll viewed i11 what l1. q I 1t we p I L'?sc, t h <'~C ('o .st' I f.c ru~ Hl_n~t. I cot JCe.L ve, b' e regnrded as moe vtel r of tH'w. spoctrs and 111 th1s r '. pc~ct {orn~ a very imporl<ltll addition to !h~ flora of the more modern geologtcal penods. lu pnssillf? from this l~cality .we~tw.ard to tl e He:tr river, Captain Fremout cro ~wd a . l11gh mo~lnt allt cl~alll, wlll<~h is the div1dittg n dg<'. between the wull_•rs o{ MtH.l~ly nver tlow111g 0.a~tward, a11d those of M11ddy creek flow. 111g 111tn Hear nver.on the wc~t. Tltc gap wlH'rc tile rid~t! Wils cro sed is ~tated to be ',200 lect above the le\rl'l or tile sea. Ill this rtdge. 115 miles to the ~~utltward of the locality ol the fossiiR Ia. t tuetltionL·d, WNe collected tl~e ~pt!?I ttt cns next to be llllmcd. Tltcsc.· Wt~rc obtained uear the summit of tlte ndgc' auu probably higher tlta11 the poi11t wltcre C;1 ptai1t Fremont's j>U rl y CI'OSH<'d. Tlte collcctio.tl f'rnm _tlli lo~ality (longitnclc 111 °, latrtncle 10°) consists of .C'''?r:tl ~pec·t1nous o( an nrgdlnceou .. , highly bitttrninou~, attLl8omcwhat :'laty lllrw:st.oue, loaded with loi-i~il_~. It. is very brittle, UltLl ca. ily shivered tilt(~ ~1nall !rngmcut. by a blow of the lHtllllller. lis natural eolor i ·a light S<~p~a, hut tt bl~acltes. on exposnrr, to lite atmosphere. 111 strueture,itisnot 1.wlli(C. some of the ltn1cstollPS of the lias or oolite CormattOII". The fossiL are cl11efly 0~1e spcctcs of Ceritl1inm aud t JJC of l\'lva; :wd be~tdes Lltese, anotlt<•r spocte ·of Cerithium and a NUt~ula can be lclcntilircl. 'o far a I u.:n a hi<! lo ascertain .. these fo ·r.;ils an· Uttdc·seribe<l, and wtll tll<'rcfore be reo-ar<.leu as new pcc1es. . Ilmay bJ considc red prenmture to dct·iJe 111 011 the p. •oln~ical position of tlu~ m:ts.-. It m~y belono· to tiiC s<un , 1wriod, thou ·~h far higher in the .. 'nrH's tlwn !hosr~ lll the .ame lnugilude, wllieh ltave ,inst been de·cribed. l11 the loeai.J(y of the fosstl plauts lhn strata clip \V. by N.; but, from tlte structnr~~ of tl.H~ comJtr~. it i:· evidl)ttt that there 1s a cku1gt! in the direction of tlt.e dtp .hcloro reaelwJg tile lu~II ridge from whicl1 thG !:ipceimens under considerattOil were tak<.:n. Fnrther examination, I have tw do11bt, will set th 1s q nest ion at r t. . l may lw_re notice tile inter sting fart of the wide extellt of 1he.e forma· t10ns sltow11l~ the ~xistcuce, in this longitude, of thes c.tlcareous bcds,of n. natnre pr~ctsely ldce those of tltc modern fonnatwu.: of we ·tern Europe. ~ few miles soutl1 of tltc locality of these fostoiil , Captai11 Frcnwnt de· 8?nbe~ the occurrence o( a11 immense stratum of fo!:isil salt; and the same ndg<' lf.l ropro~ented as bouudiug LlJC Great Salt Jake. 'T'Iwre wonld there· fo~·e e<~~n uo d.onht that tho salt iu question is associated with thf' strata of th1s pertod, aud probably coeval w1th the same. l may remark, in the same connexion, that the surfaces of the specimens 2~9 [ 174 J . · ,., the fnc:~il ferns nJ.,o < · mnn~.;;rc a ~~ 11; whic·l~ JS apparently clJioc~ ntaitndium. Thi · fact snr•ms to indiratr' rlt presetiCe of fos~il Ralt at rtt~e J· ~~nee north of tlw known localily, aucl is a circuulslHnc;c which we thts .1natut as lly "'P[Hopriate ns pn rt of the evidence of identity iu the age of tlw (.0. formal ions. . . . 'l'l 's 111 -><rion is nnc.1ncstioual>ly one of the l11ghest Illlt>rc:-.t, l>oth a::, regardt-\ et> · 1 II . l ·1 . I . t . . I L . 1 s economical resources, auu eq ua y so .1n t tc cotttn mt wtts w 11C1t It ~ 1 1 icltl to crculogical s~ie1!cc. In tl\n s p~ctnwns f~·olll t ~I<: v<·.~e~:t!Jic localtty '· lhuve b~cn able to !lldJcate . even or <'Ight specu~s of fossil fcrm;, 1nost of 1. 1 arc ucw. Futthcr ruseartltes will <.Junbtlc .. · greatly multiply tlu~ nwml iCu bIc r. Besides tile. c, as 1_1ew spuc . I I l ,. . 1 tcs pro 1 )a> 1 y pec'tt 1ar to our ~·<lHtttnent 1 ltn.ve a higher i11tcrest, llt::ISillttc: 1 as I lCY ~lOW to ns tile Wit e cxteut ~ 17th~ nature of tile vco- tatio11 of' this uwcJern coal p 'rio<.l. In the broad !flilelUld of the west we shall have • 1' . . I d cllt opportuutty o tractlll5 1t over arge an unb;okcu areas, ~nd m~uy lti.ghly illterc~titJg. '.'esnlt~ lll:~y follow its com-arison with til' vegetation of tl1c true ~arhOtl l ( ·rou~ p(.;l'!Od . p Again: since the c dcposile~ have CVlde!ltly been mauc (!V (' l' '·(ll'ge tr:~cts ofcountry, it i~ not lllll'Cason:tble to Ktlppmw tlwt tit<: qtwntll~ ol tllittcnal::; accumulateJ wi!liJc very great, artd t!Jat we tuc.1.y expect to f11 1d proftta~le coal beds ill tile rocks of thi ~ age. This !'lnhject, lw~id es Lei11g of lugh interest to science, is of ·omc prospective ecotJOtllical iutp(~rtanee,. thongl1 perhaps too n·uwte to elwell upou, wltile the country renw.1us ~o httll.! ex-plored a' at pre~cnt. . , . . ~ . . Lonnitud • lUZ0, latitude 42°.-1 he 5p<:CllttCll No. 72 Js a o-rny 1~;h blue limeslt~te, efllorcscing a .. alt upon tltc ~urface, '· fro1u the Ilot Salt Spri.ug~ of 'eptember 13, 1843." No. 108 i~ a siliceous liwestuu<: of'\ IJt·owut.sllgray color; where expo::~ 'd, the sur1acc beeo111e poron. , fro.m lrH~ solut1011 and removal of the lime, wllilt' the si liceous particles rennuu. From tlte oeueral lithulo nical cbaructers of tiLe Sl)(.Witncn, it is prohahly a rnoder11 b ':> rock, but it~ preci 'C age CUlJIJOt be uccid.ed. Longitude 11 2°, latitude -112°.-TI!c single ~pecitw~ll fron1 ll1is .locullt) is, in it, prc.eut ·tate," g rauular quart'l.." It i~ however, very cv.ld.~ntly au altereu ~cdimcutury rock, witlt the li11c~ of depositio11 gnitc distll~ctly preserVl'd. This rock probably eou1cs ont from llltder the ~i l iccon lt~ucstonc la!:lt Ul'S<.:rihcd both havitig l>eeu alwred by modern ig1tcous actwu . The cltamctPr of the .. pecimcns fr01n the next locality-three-quarter::; of a degree farther wcst-l1H1.Y pcrlwps throw sOH Jc li~llt upou tlte present condition of those la~t named.. Longitude ll2J0 , latitude 42J0 ; at 1 he .flmc?·ica n Fulls of ;Snalc~ riue'r.Titccollectiou from this poiut presents the folluwiug, ill a ue~Cclldlllg order. These specimcus are uun1Lered 9'1, !Ju, 97, 101, 10~, lOG, attd 107: I. A bnlryoidal or coucretionarv ta va, No. 9 J. 2. Oh idian, No. 102. - 3. Vitrified sandstone, No. lOG. I. A wlliti ·It a~h-colorcd clJ;lll or limestone, No. 101 . 5. A light ashy volcuuic sat1<.l, No. 97. ?· Brown . a11d, volcanic. (?) . . l'lw~e are all apparent I y volcau ic product--~ WI tit, prolmbl Y, the exception o! Nos. 106 aU<l 107, which may be seduucu.tary products~ the firs~ altered by heat. The two lower depo::>itcs are evtc1ently volcau1c san~ or "ash_cs;" the upper of these or No. 5, has all the characters of pnlvcnzcu punuce stone and is <.lonbtlcs ... of similar origiu. •• |