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THE PLIOCENE AND PLEISTOCENE DEPOSITS OF MARYLAND 



the rrnid deposit in the lagoon had actually reached the level of wave 

 work and had transformed the lagoon from a pond to a marsh or meadow, 

 the breakers attacked the upper portion of the lagoon deposit and denuded 

 it down to the level of wave base as rapidly as they could reach it from 

 under the superficial veneer of the beach sands. Cypress, ferns, sedges, 

 and other vegetation which had taken up their abode in the marsh would 

 be overwhelmed with detritus by the advancing beach and a little later 



Fig. 8. — Diagram showing later stage in advance of Talbot shore-line. 



■would be destroyed by the breakers. In this way all traces of life must 

 have been removed from the deposit except such as happened to occupy a 

 position lower than wave base. One, therefore, finds preserved in the 

 clay water-logged trunks and leaves, nuts, etc., and roots of huge trees 

 like the cypress which would tend to sink by their great weight further 

 and further down into the soft mud as the trees increased in size. The 

 areas over which the waves had removed the upper portions of the lagoon 

 deposit can be determined not only by the presence of truncated stumps 



