IV] 



PRESERVATION OF PLANTS 



65 



Plants which owe their preservation to amber 

 occur both as incrustations and petrifactions. This 

 fossil resin occurs in Tertiary, Cretaceous, and 

 Jurassic rocks ; the amber found in abundance on 

 the Baltic coast near Danzig and occasionall}^ picked 

 up on the beach in Norfolk and Suffolk comes from 



Fig. 8. Flower of Cinnamoum prototypum Conw. preserved in 

 amber. x 10. (After Conwentz.) 



beds of Tertiary age. Pieces of Pine-wood have been 

 described from the Baltic beds in which the tissues 

 are perfectly preserved as the result of the conversion 

 into amber of the resinous secretion which permeates 

 their cells : in this case the amber is a petrifying 

 s. 5 



