752 



FLORA OF THE TERTIARY PERIOD. 



In some of the tertiary formations there occur pieces of wood, which 

 present the structure of that of Pepper-plants and of Palms (figs. 940, 

 941), and there are also leaves which have the flabelliform appearance 





Fig 935 



Fig. 936. 



Fig. 938. 



Fig. 939. 



of Palm leaves, included under the name of Palmacites (fig. 942). 

 Specimens allied to Chara are also found, with their fructification 

 denominated Gyrogonites. 



The Tertiary period is characterised by the abundance of Angio- 



Figs. 935-937. Structure of ordinary Dicotyledonous stems, to illustrate the appearances 

 presented by some tertiary fossil woods. Fig. 935. Portion of a Dicotyledonous (Exo- 

 genous) stem- cut transversely. Natui'al size. Fig. 936. Section of the same magnified, 

 to show the occurrence of large porous vessels. The ordinary Dicotyledons differ in tliis 

 respect from Conifene. . Fig, 937. Longitudinal section of the same in the line a b, per- 

 pendicular to the medullary plates, showing woody tissue and large pitted vessel, and the 

 rays appearing here and there among the woody tissue. Fig. 938. Leaf of fossil Elm of 



the middle Tertiary epoch. Fig. 939. Leaf of Comptonia acntiloha, an Amentiferous 



plant of the same epoch. 



