Anonymous • The Study of Fossil Plants 



215 



ANGIOSPERMS 



It is in this group that the bulk of 

 our famihar hving plants belong, so 

 that it is obviously unnecessary to go 

 into any detail concerning them. 

 Angiosperms represent the culmina- 

 tion of the much branched plant line 

 of ascent. They were the latest to come 

 upon the earth and some are perfectly 

 adjusted to a terrestrial existence. 

 Angiosperms appeared during the 



Lower Cretaceous and have been domi- 

 nant among plants since Tertiary times. 

 It is estimated that they arc represented 

 by about 300,000 living and several 

 thousand fossil species. The rapid rise 

 of Angiosperms is thought to be due 

 in part at least to the development of 

 the flower-loving insects such as the 

 bees, wasps, and butterflies in the Ju- 

 rassic, the period just preceding that 

 which marks Angiosperm beginnings. 



QUESTIONS 



1. What importance does Paleobotany 

 have for students of earth history? 



2. How are plants preserved as fossils? 



3. What were the fossil relatives of the 

 "horsetails"? 



4. Mention two fossil relatives of our 

 lycopodiums and selaginellas. 



5. What groups might be included in the 

 Pteropsida? 



6. Name and characterize one of the fos- 

 sil gymnosperms. 



7. Trace the history, geologically speak- 

 ing, of the angiosperms. 



