158 BULLETIN OF THE MUSEUM OF COMPARATIVE ZOOLOGY. 



the outcrops of these fossil reefs at the southern extremity of the Everglades 

 are only outlyers of the southern extension of these northern rocks. To the 

 damming up of the waters in the Everglades, and to the sudden outbursts of 

 gigantic masses of water charged with organic matter and lime, we may trace 

 the immense destruction of fishes which so frequently occurs on the shores of 

 the Florida keys and the waters surrounding them. 



ALEXANDER AGASSIZ- 



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