PAPERS OX GEOGRAPHY AND GEOLOGY 331 



It is possible also that this depth (21 feet) marked the 

 base of the mound and these shells may have lived in a 

 swale on the original site of the mound. Three species 

 were found, as follows : Physa gyrina Say, Planorbis tri- 

 volvis Say, Lymnaea reflexa Say. One specimen of Plan- 

 orbis trivolvis was found in the upper eight feet of the 

 mound. This must have been contained in the material 

 used in erecting the mound. 



Professor M. M. Leighton collected several shells from 

 other mounds during his geological examination of this 

 region. These are noted below. Planorbis trivolvis Say, 

 Segmeniina armigera (Say), Lymnaea palustris (Mull.) 

 (fresh water shells) : Eelicodiscus pa rail el us (Say), land 

 shell. From Sam Chiucallo's Mound, on outskirts of East 

 St. Louis, 111. These probably were included in building 

 material. 



Physa gyrina Say, Vivipara contectoides W.G.B., An- 

 odonta grand/is Say. 



Fresh water snails and paper shell clam from the 

 Kunnemann Mound. These probably were included in 

 building material. 



Nineteen species of fresh water shells are listed 

 above as occurring in the mounds and as being used by 

 the Indians for some purpose. Seven additional species 

 probably were included in building material. The first 

 mentioned species doubtless were used largely as food, 

 for the ancient aboriginee, like his more modern descend- 

 ant, probably esteemed this bivalve as a valuable part of 

 his menu. The curious and brightly colored shells of the 

 clams and the form of the snails doubtless attracted his 

 attention and suggested ways in which they could be used 

 for practical use as well as for bodily ornamentation. 

 The shell gorgets and effigies also indicate that the large 

 flat surface of some of the mussels created an art impulse 

 which is reflected in these curious objects. 



MARINE MOLLUSCA 



That the Mound Builders and other aboriginal inhabit- 

 ants of America were traders is evidenced by the pres- 

 ence of many marine shells which evidently came from 

 the west coast of Florida or from the Gulf coast of the 



