SHELLS OF ORMOND MOUND. 171 



10. Vivipara georgmna Lea. A few specimens of 



this southern fresh-water univalve were scat- 

 tered through the upper half of the mound. 



11. Ampullaria, depressa Say. This is another 



fresh-water shell, which is abundant in the 

 St. John's River and its tributaries. Accord- 

 ing to Wymans, it forms a large proportion of 

 the fresh-water shell mounds along that 

 stream. In fact, he states that it, Paludina, 

 multilineaia, Say and Unio ~buckleyi Lea, are 

 the three species which form these mounds. 

 He then adds: "Either of these species, in- 

 stead of being promiscuously mingled with 

 the rest, as is generally the case, may be 

 found forming considerable deposits by them- 

 selves, without the admixture of the others, 

 as if at certain times they had been exclu- 

 sively used for food." 



This is true of the Ampullarias in the 

 mound at Ormond. They were found in but 

 three different places, about a peck in each 

 place, and nowhere else. We can suppose, 

 therefore, that some visitor, or member of the 

 party here encamped, returning from an in- 

 land stream brought an occasional supply of 

 these fresh-water mollusks with him as a vari- 

 ation of diet for his dusky brethren. After 

 serving up the animals as foo<l, the empty 

 shells were dumped into one place 011 the re- 



