THE PLIOCENE PERIOD. 



297 



Fig. 459. — Map showing the distribution of the better known parts of the Pliocene 

 system. The conventions are as in other maps, except that the area of the Laray- 

 ette, along the Atlantic and Gulf coasts, is marked by vertical dashes. This for- 

 mation is doubtless more wide-spread than the map shows, as indicated in the 

 text. Relatively little of the exposed Pliocene is marine. 



