80 Heign of Angiosperms. 



But in southern Sweden, at Kopingue in Scania, some speci- 

 mens of dicotyledonous leaves appear associated with a 

 species of Cycadeae, in beds which have been referred to the 

 greensand ; so that the whole Chalk formation would appear 

 to constitute a first period in the reign of the Angiosperms, 

 forming, so to speak, the passage between the vegetation of 

 the Secondary and that of the Tertiary formations, still pre- 

 senting, as the first, a few Cycadese, as the following, some 

 Angiospermous dicotyledons, and thus paving the way to the 

 considerable development of these vegetables in the succeed- 

 ing period. This period is besides characterised by many 

 Coniferae peculiar to it, and which appear very distinct from 

 those of the Wealdean formations, and from those of the 

 Eocene epoch of the Tertiary formations ; and such in par- 

 ticular are the Cunninghamites. 



" We can therefore distinguish tw^o great periods in the 

 reign of the Angiosperms : 



"1*^, The Cretaceous period, a kind of period of transition. 



" 2c?/y, The Tertiary period, presenting all the characters 

 arising from the predominance of Angiosperms, Dicotyle- 

 dons, and Monocotyledons, and divisible into many epochs, 

 the characters of which will not be well established until we 

 have removed all doubts as to the agreement of the different 

 local series of the Tertiary formations. 



" V. Cretaceous Period. — The Cretaceous period, properly 

 so called, comprehends perhaps many distinct epochs ; but the 

 beds where fossil vegetables have been observed, not having 

 been always classified with precision in the different subdivi- 

 sions of this formation, it is impossible to establish their 

 chronology with certainty. Besides, we must distinguish an 

 epoch which appears immediately to precede this formation, 

 and one which follows it, and yet differs from the Eocene 

 period. 



** We are acquainted with fossil vegetables of the Creta- 

 ceous period : — 



" 1*/, Sub-Cretaceous Epoch. — In the subcretaceous marine 

 lignites of the Isle of Aix, near La Rochelle, and of Pialpinson, 

 in the department of the Dordogne ; these are the most an- 

 cient beds of the Cretaceous formation, or the last of the 



