( 349 ) ^ 



General Considerations on the Nature of' the Vegetation which 

 covered the Surface of the Earthy at the Different Epochs of 

 the Formation of its Crust : Agreement of Antediluvian 

 Botany and Zoology ; and Conjectures relative to the Aspect 

 of the Earth, and the Temperature of its Atmosphere, dufi- 

 ing these Different Epochs. By M. Adolpiie Brong'- 



^ NIART *. 



JLhe ardour with which naturalists have engaged since the 

 commencement of the present century, in collecting materials 

 for the physical history of the formation of the crust of the 

 globe, brings us every day nearer to the period when we shall 

 be able to trace with precision the history of the various stra^ 

 that have l)een successively deposited at its surface, and of the 

 animals and vegetables which have lived, whether in the seas 

 that covered it, or upon the dry parts of this surface. 



We have not yet, however, attained this object, towards 

 which ought to be directed all the efforts of the geologists and 

 naturahsts, who, by their researches, labour to throw light ujx)n 

 the history of the organised beings of the primitive world ; but 

 it is useful from lime to time to exhibit a picture of the state of 

 science, to show the solid results which have been attained, to 

 point out the doubts which remain to be solved, or the voids 

 which it may be hoped to fill up. By this means, a moi:e use- 

 ful direction may be given to our inquiries, by fixing as it were 

 the points around which the new discoveries may be arranged^ 

 This is the object which I have in view ia.tjje.^|^i]paenti memoir, 

 with respect to the history of fossil vegetables,, 'con^d^red witfj 

 reference to the relations that exist between the. periods duij^ 

 ing which they have lived, and the botanical characters which 



they have presented. .;,(;! . . ; »' ; • , ,':;fr. *[\ -innf) 



Perhaps no department of natural bistory has- made more^ra-r 



pid advances within these ten years, and our acquireiheuts^pj^ 



this subject are very different from what they were in 1822, 



• We have great pleasure in presenting this important, memoir of our 

 young friend Brongniart to the attention of naturalists. The views it con- 

 tains are similar to those we have hccw in the jjractice of delivering to our 

 pupils in the University, both in the class-room and during our geological ox- 

 cursions....,EDiT. 



•JANUARY — MARCH 18S9 ..«..^„«,v.m ..^..... X « 



