294 



Origin of Biomes and Succession 



result, these species disappeared from the area. The grasses and other 

 herbs now constituting these grassland biomes may very well be 

 the only members of the old biomes which were hardy to both the 

 new cold and the new xeric conditions. It is also likely that these 

 species were members of the subclimax communities of the older 



Fig. 128. Occurrence of present California woodland and chaparral (black) 

 and records of related Cenozoic vegetation (numbered dots). (From Axelrod.) 



