266 



Notices of Memoirs — Count de Saporfa — 



In the second part, the author reviews in succession the Vegetable 

 Periods, which he divides as follows : — 



Geological 



Stages. 



Phytological 







Phytological 



Formations. 

 Primordial 



Laurentian. 



Epochs. 

 ( Primordial 





i 



Periods. 



or 



Cambrian. 



] or 







Primordial. 



Protozoic. 



Silurian. 



( Eopbytic. 





, 



r Devonian. 





Devonian. 



/ Carboniferous 







Palseantbracitic. 



Paleozoic. < 



Carboniferous. 



< or 





- 



Carboniferous. 



( 



Permian. 



( Palseopbytic. 







Supracarboniferous 

 ^ Permian. 





r 



{ Bunter. 







' Triassic. 





Triassic. 



] Mushelkalk. 



>-. 



o 









( Keuper. 





"£> 



Infraliassic. 



Mesozoic 

 or < 



Jurassic. 



( Lias. 

 { Oolite. 



>1 



8 f- 



Oolitic. 



Secondary. 





/ Neocomian. 



oq 



H 



Wealden. 





Cretaceous. 



\ Cbloritic Cbalk. _ 

 j Eouen Cbalk. 







k Urgonian. 

 ' Cenomanian. 





w 



\ Upper Cbalk. 





o 



Supracretaceous. 









P~> 



-$■* 



Palasocene. 









>i 



o^< 



Eocene. 



Neozoic 



Eocene. 





Eh 



o 



Oligocene. 



or 



Miocene. 





£ 



Miocene. 



Tertiary. 



Pliocene. 



. 







^Pliocene. 



In the first chapter of the second part the author reviews the 

 vegetable contents of the various formations. The earliest traces 

 are marine, the Bilobites (Cruziana) rugosa, D'Orb., being a true 

 Alga? from the Silurian ; Harlania Hallii, Goepp., Chondrites fructi- 

 culosus, Goepp., Murchisonites (Oldhamia) Forbesi, Goepp., from the 

 Irish Silurian, and Spirophyton, Hall, of America, belonging to the 

 same category. He comments on the plants of the Lower Silurian 

 being purely marine, and figures the oldest terrestrial plant, Eopteris 

 Morierei, Sap., discovered by Prof. Moriere in the slates of Angers, 

 in the zone of Calymene Tristani (base of Middle Silurian), a Pern 

 near to Cyclopteris of the Coal-measures. In America M. Les- 

 quereux, and in Canada Principal Dawson, have recognized Spheno- 

 phyllum from the Upper Silurian, the species being S. primcevum, 

 Lqx. Lesquereux has also described Protostigma sigillarioides, Lqx., 

 and a Lycopodiaceous plant, JPsilophyton, has been recognized by 

 Dawson, with affinities leaning towards the Ferns through Hymeno- 

 phyllum, with the Ehizocarps through Pilularia, with the Lycopods 

 through Psilotum. Psilophyton also occurs in the Devonian of Canada, 

 with Asterophyllites, Annularia, Galomendendron, Lepidodendron, and 

 ferns. 



Before describing the Coal-measure flora, the author notices the 

 formation of modern peat-mosses, and points out the conditions 

 necessary for their production, the most important being an equable 

 temperature, constant humidity, a flat country allowing free access 

 to water supported by an impermeable soil, and a moderate amount 

 of heat, peat-mosses not growing south of the 40th parallel. 



