71 



printed on the back of the photograph reads, "Skull of 

 'a Mound Builder' from shell-bed on Rock Island." Mr. 

 Tiffany, in his letter accompanying the photograph, states 

 that there were six other skulls found in the "shell-bed," 

 and also a plate of mica and several other articles. The 

 following description of the locality in which the skull 

 was found accompanied the photograph : — 



"The skull known as the shell-bed skull was discov- 

 ered by A. S. Tiffany in Nov., 1871, and contributed by 

 him to the Davenport Academy of Natural Sciences, with 

 description. 



On the Rock Island Arsenal grounds, near the western 

 extremity of the island, there had been an excavation 

 about three hundred feet long and eight feet deep. Three 

 feet from the top there was a deposit of shells, mostly 

 species of Unio, Melania subsolida, and two or more 

 species of Helix. The shell-bed at this place varies from 

 six to sixteen inches thick. 



In this shell-bed the skull and bones belonging to one 

 individual were found ; all the covering above the bones 

 was an aqueous deposit ; above the shells, as well as with 

 them, there were water-worn pebbles and sand, the mate- 

 rial becoming finer towards the top, the last foot being 

 fine alluvium and vegetable mould ; the sedimentary lines 

 were perfect and unbroken. The excavations had made 

 the means of observing all that could be desired. 



The place was visited by many members of the Society 

 and by Prof. Alexander Winchell, while some of the bones 

 were in place, and all agree that the soil covering this 

 prehistoric man was a sedimentary deposit. 



Accurate levelling proves the top of this deposit to be 

 eighteen feet above the highest water known in the Mis- 

 sissippi since Fort Armstrong was established on the 

 island." 



Mr. Putnam thought that the indications were that the 

 relics were those of the ancient Indians rather than 

 Moundbuilders. He did not know of any shell-beds 



