Abstract
During a number of years past the writer and his wife have made frequent visits to the desert ranges in the central part of the Colorado Desert, California. A search for land shells has been made in every locality visited, with varying success. The total collection of Micrariontas obtained to date, although by far the most complete from the region, still lacks specimens from many localities. A study of this collection, however, has brought to light some interesting facts in distribution which may be worthy of record.