1S38] 



FARMERS' REGFSTER. 



829 



crantick irrou'tli; wliich was an ossential cliamctcr- 

 istick of this primitive creaiion.* 



After the (lestrui'tion of this primitive vcifeta- 

 tion, the vejTelable kinirdoni appears for a loiiij pe- 

 riod not to have attained the same detrree of deve- 

 lopment. Indeed, in the numerous layers of se- 

 condary earths which succeed the coal formations 

 we scarcely ever find those masses ol vegetable 

 imprints, a species of natural herbariums, which, 

 in these ancient depots of carbon, attest to us the 

 eimultaneous existence of a prodigious number of 

 plants. Scarcely in any part of these formations 

 do we meet with thick layers of fossil combusti- 

 bles; and never are such layers often repeated, or 

 found of such great extent as in the coal deposits. 

 Either the vegetable kuigdom at this period ocim- 

 pied more circumscribed portions of the surface of 

 the earth, or its scattered individuals covered but 

 incompletely a soil of little fertility, and of which 

 the revolutions of the globe had not permitted 

 them to become tranquil possessors; or, finally, 

 the condition of the surface of the earth was not 

 favorable to the preservation of the vegetables 

 which then inhabited it. 



Yet that long period which separated the coal 

 from the tertiary formations, a period that was 

 the theatre of so many physical revolutions of tlie 

 globe, and which witnessed the appearance, in 

 the waters ol" the deep, of gigantic reptiles, types 

 of the fantastical organizations in which we may 

 suppose we often recognize those monsters born 

 of the imaginations of the poets of antiquity; this 

 period, f say, is remarkable in the history of the 

 vegetable kinirdom, by the preponderance of two 

 families vvhich are lost, so to speak, in the midst of 

 the immense variety of vegetables with which 

 the surface of the earth is covered, at the present 

 day, but which then predominated over all the 

 others, by their number and their magnitude. 

 These are the conifcroi, of which the fir, pine, 

 yew and cypress furnish well known examples; 

 and the cycadecB, vegetables wholly exotick, less 

 numerous at the present day, than at this ancient 

 period, and which joined to the leaves and mien 

 of the palms, the essential structure of the coni- 

 ferag. The existence of these two families, du- 

 ring this period, is of high importance as signal- 

 izing an intimate relation between them, by^heir 

 organization; and they form the intermediate link 

 between the vascular cryptogamia, which com- 

 posed, almost alone, the primitive vegetation of 

 the coal period, and the phanerogamick dicotyle- 

 dons, strictly speaking, which constituted a ma- 

 jority of the vegetable kingdom, during the terti- 

 ary period. 



Thus, to the vascular cryptogamia, the first de- 

 gree of ligneous vegetation, sijcceeded the coni- 

 fers and the cycadea?, which held a ratik more 

 elevated in the vegetable scale; and to these last 

 succeeded the dicotyledonous plants, which occu- 

 py the summit of that scale. 



In the vegetable kingdom, as in the animal, 

 there has been, then, a gradual improvement in 



the organization of the beings which have suc- 

 cessively existed upon our earth, from the first 

 which appeared upon its surface even to those that 

 inhabit it at the present day. 



The tertiary period, during which were deposit- 

 ed those earths that now fiirm the soil of the prin- 

 cipal capitals of Europe, as London, Paris, and 

 Vienna, witnessed transformations, in the organ- 

 ick world, greater than any of those which had 

 taken place since the destruction of the primitive 

 vegetation. 



Fn the animal kinudom : the creation of mam- 

 niilers,* a class which all naturalists concur in 

 placing at the summit of the animal scale, and by 

 which nature seems to have preluded the creation 

 of man ; in the vegetable kingdom, the creation 

 of the dicotyledons, a grand division which, by 

 unanimous consent, botanists have always placed 

 at the head of this kingdom, and which, by the 

 variety of its forms and organization, by the mag- 

 nitude of its leaves and the beauty of its flowers 

 and its fruits, must, of necessity, have imprinted 

 upon vegetation, an aspect very difi^erent from 

 that which it had ofiijred through all previoug 

 periods. 



This class of dicotyledons, of which we are 

 scarcely able to cite any indications at the close of 

 the secondary, presented itself; all at once, during 

 the tertiary period, with preponderating influenced 

 It then, as at the present day, held doniinion over 

 other classes of the vegetable kingdom, both in re- 

 ference to the number and variety of the species, 

 as well as the magnitude of the individuals. 

 Thus the assemblage of vegetables which inha- 

 bited our climes during the deposition of the terti- 

 ary formation, which enveloped their ruins in its 

 sedimentary layers, were intimately allied to the 

 ma.^is of our present vegetation, and more parti- 

 cularly to the flora of the temperate regions of 

 Europe and America. The soil of these countries 

 was covered then, as at present, with pines, firs, 

 culms, poplars, birches, elms, walnuts, maples, and 

 other trees almost identical with those which stili 

 flourish in our climates. 



And yet, not only do we not recognize any 

 indications of those singular vegetables which 

 characterized the primitive forests of the coal pe- 

 riod, but we rarely encounter, there, even fragments 

 of plants analogous to those which now vegetate 

 between the tropicks. 



VVe do not, however, necessarily infer that the 

 same vegetable forms have been perpetuated from 

 this epoch, still very ancient, (since it preceded the 

 existence of man,) to the present day. No: very 

 sensible difl'erences almost always distintruish these 

 inhabitants of our globe, very recent, geoloirically, 

 but exceedingly ancient, chronologically, from our 

 cotemporaneous vejjetables to which they seem 

 most nearly allied ; and the existence in these same 

 earths, in the north of France, of palms, very 

 different from those Avhich still vegetate upon 

 the borders of the JMediterranean, and of a small 



* We find, it is true, in some parts of the secondary 

 formations, a small number of arborescent ferns and 

 of the gigantick equiseta; but yet of a stature much 

 less considerable than those of the coal formations ; 

 nor do we discover, there, any trace of the arbores- 

 cent lycopodiaceae analogous to the lepidodendrons.— 

 Author's note. 



Vol. VI.— 42 



* In placing the first appearance of mammifers at 

 the epoch of the tertiary formation, I do not include 

 the fact, unequalled elsewhere, of the fossil mammi- 

 fers of Stonesfield; a case which forms an exception to 

 all former experience, and which cannot be detailed in 

 so limited an essay. — Author's note. 



For drawings and brief descriptions of these fossils, 

 which occurred in oolite, see Lyell's Geology, Ameri- 

 can edition, Vol. I, pp. \oi-^.— Translator. 



