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Show 148 THEORY OF and the lapidifying process has often effaced not only the characters by which the species, but even those ~hereby the class might be determined. The number of orgamc forms which have disappeared from the oldest strata, may be conjectured from the fact, that their former existence is in many cases merely revealed to us by the unequal weathering of an exposed face of rock, by which certai~ parts are made to _stand out in relief. As the number of species of shells found m the English series, from the graywacke to the coal inclusive, after attentive examination, amounts only to between one and two hundred species, we cannot be surprised that so few examples of vertebrated animals have as yet occurred. The remains of fish, however, appear in one of the lowest members of the group*, which enth·ely destroys the theory of the precedence of the simplest forms of animals. The vertebra also of a saurian, as we before stated, has been met with in the mountain limestone of Northumberland t, so that the only negative fact remaining in support of the doctrine of the imperfect development of the higher orders of animals in remote ages, is the absence of birds and mammalia. The former are generally wanting in deposits of all ages, even where the highest order of animals occurs in abundance. Land mammifera could not, as we have before suggested, be looked for in strata formed in an ocean interspersed with isles, such as we must suppose to have existed in the northern hemisphere, when the carboniferous rocks were formed. "' Numerous scales of fish have been found by Dr. Fleming in quarries of the old red sandstone at Clashbinnie in Pet·thshil'e, whel'e I have myself collected them. These beds are decidedly older than the coal and mountain lime-stone of Fifeshire. t I do not insist on the abundant occurrence of the scales of a tortoise nearly allied to Trionyx, in the bituminous schists of Caithness, and in the same forma· tion in the Orkneys in Scotland, as another example of a fossil reptile in rocks as old as the carboniferous Heries ; because the geological position of those schists is not yet determined with precision. Professor Sedgwick and Mr. Murchison indeed infer, that they alternate with a sandstone of the age of the old red sandstone; but this opinion wants confirmation. The numerouH fish, and the tortoi11e of Caith· ness, are certainly in strata older than the lias, for that rock rests upon them uncon· formably; but as the strata between the schists and the granite contain no organic remains, and as no fossils of the carboniferous era have yet been found in the Caith· ness beds, the relative date of the tortoise cannot be determined with confidence. It might possibly be of the age of our magnesian limestone. See Geol. Trans. second series, vol. iii., part 1, p. 144, and for a representation of the scales of the 'l'rionyx, plate 16 of the same part. SUCCESSIVE DEVELOPMENT. 149 As all are a()'reed that tl . subaqueous anl £or tile 1e ancwnt strata in question we!·e ' most part b · f we may ask do naturalists i c I su mannc, rom what data · nJ.er t 1e non existe rarity of warm-blooded uadru , . - ~ce or even the they dredged the bottomq f th peds u;.,:he earber ages? Have · . 0 e ocean ~hrou h t extensive With that no'"' occup1.e d by th gb ou. an area co-and 11ave they found that 'tl h e car omferous rocks I WI 1 t e number of b t ' two mndred species of shells the al w . e ween on~ and at least one land quadru ed? /u ays obta111 t.he remams of report that on sounding i!the Inditpose our ~anners were to and at some distance from the la:;cean neat some coral reefs, attached to their line portion f 1 ' they drew up on hooks should we not be sceptical as t~ ~he a eopard, eleph.ant, or tapir; and if we had no doubt f tl . acc.uracy of their statements . o leir veracit · h ' t?em to be unskilful naturalists ? or i~' :lg t we not suspect tloned, shou Jd we not be dis os ' . t e fact were unq uesbeen wrecked on the spot ~ ~.rl ed to beh~ve that st~me vessel had whereby land quadruped's le casualties must be rare indeed . are swept by r' d mto the sba, and still rarer ~t b l I:ers an torrents fl · mus e t 1e contmg f no ha tmg body not bein()' dev db h ency o such a 0 oure y s arks or oth d s , such as were those f h. h er pre a ceo us in some of the carbonifero~s ;r~~ *we find. the teeth preserved escape and should happen t . la . h But zf the carcase should f 0 sm < w ere sedim t · act o accumulating and if th en was 111 the disintegration should not ffi e n~merous causes of subsequent for countless ages in solid eroa~e? .:races of the body included tion of ~hances that we shou~d' ~i: unot contrary to all calculamere pomt in the bed f tl . pon the exact spot,-that l . 0 le ancient ocean 1 . h . re Ic was en tom bed ~ C ' w lei e t e precious I · an we expect for 1 we Jave only succeeded 'd a moment t lat when corals and shellc:z in fi d' am; st several thousand fragments of · ~, n mg a J.ew bones of t' ammals, that we should m t . 1 . aqua zc or amphibious bitant of the land? ce Wit 1 a single skeleton of ~n inha- Clarence, in his dre arn, saw " 1.1 1 the sh. my bottom of the dee , --a thousand fearful wrecks . p, ~ t~ousand men, that fishes gn~w'd upon. Had he e ges of gold, great anchors, heaps of p~arl. • also beheld amid " tJ le d ea d bones that lay scatter'd from I thhe ave see n 1·1 1 the collection of Dr Flemin th mountain limestone of Fifo, wbi~b altcrn!tes ~i:~e!~e ~~a~~vorous fish |