32 TRANSACTIONS OF THE WAGNER FREE 



tributaries of Big and Little Sarasota Bays, and more particularly those 

 exposed on the Caloosahatchie, conclusively proves that a coral extension 

 to the southern United States, such as had been theoretically set forth, 

 does not exist in fact. To be sure, remains of coral structures, possibly 

 representing even true reefs, were found at various points, as for example 

 at Ballast Point, Hillsboro Bay, and on White Beach, Little Sarasota 

 Bay, but these limited structures are evidently only of local formation, 

 and indicate a period when a fringe of coral developed where, through 

 unfavorable circumstances, probably induced through a lowering of the 

 temperature, structures of a similar kind are no longer represented. In 

 other words, they indicate nothing more or less than is indicated by 

 remains of a like character found in our more northern Miocene deposits 

 the masses of Astrsea, etc., of North Carolina, the James River, and 

 other localities. Along the Caloosahatchie we found only scattered 

 clumps of coral (Astraea, Colpophyllia, Dichocoenia ?), measuring possibly 

 eight or ten inches in greatest extent, and nothing that could be taken to 

 indicate an associated reef. 



In conformity with the system of nomenclature which I have else- 

 where adopted in the classification of the American Tertiary deposits, I 

 would propose to designate the Pliocene series of the Caloosahatchie as 

 the " Floridian," by this name indicating the region where the formation 

 has its furthest, and, as far as we know, only, development. What its 

 precise equivalent among the trans-Atlantic formations, if any such 

 exist, may be, still remains to be determined. Thus far I have been 

 unable to discover any whose fauna can be strictly, or even approxi- 

 mately, correlated with the present one. Besides shells and corals, and a 

 few hypothetical remains which are perhaps to be referred to the class of 

 annelids, the only other invertebrates found in the banks were several 

 more or less perfect specimens of the large urchin, Echinant/iiis rosacats. 

 Two of the more remarkable of the molluscan forms occurring here are 

 an ark, differing from all known types of the family, whether recent or 

 fossil, in a peculiar anteriorly projecting spout or rostrum, and a cowry, 

 with a singular channeled apex. 



For some distance below the Fort Thompson rapids the topmost of 

 the marine deposits exposed on the river the Post-Pliocene Venus can- 

 cellata bed already referred to is seen to be overlaid by a heavy stratum 

 of limestone, in which the remains of fresh-water organisms, Planorbis, 

 Limnea, etc., are very numerously imbedded. This fresh-water lime- 

 stone, in many places an absolute shell-rock, compact but largely water- 

 worn, can be traced with few breaks to the rapids (and beyond), where it 

 acquires its maximum development, with a thickness of two or two and 

 a-half feet. It here rises from two to four feet above the surface of the 

 water, everywhere overlying the Venus cancellala bed, which in turn here 



