Vaught (1989) puts Columna in Achatinidae.
Dr. David Campbell
"Old Seashells"
Biology Department
Saint Mary's College of Maryland
18952 E. Fisher Road
St. Mary's City, MD 20686-3001 USA
[log in to unmask], 301 862-0372
Fax: 301 862-0996
"That is Uncle Joe, taken in the masonic regalia of a Grand Exalted Periwinkle of the Mystic Order of Whelks"-P.G. Wodehouse, Romance at Droigate Spa