1. Map of the original swamp areas of the lower peninsula of Michigan.: 1907. Compiled from John Farmer's map of 1873 for report Maps University Of Michigan Public content 1907. Michigan. Geological Survey Division. By C. A. Davis on peat. From Geological Survey of Michigan. Annual report for 1906. Plate XVI. Swamp areas shown in brown. 1 map: col.; 64 x 52 cm.