PLATE LXIX. 
1, Littorina angulifera, twice natural size. 4, Cerithium floridanum. 
2, Littorina scutulata, much enlarged. 5, Cerithium muscarum. 
3, Littorina planaxis, enlarged. 6, Cerithidea scalariformis, enlarged. 
7, Cerithidea sacrata. 
