Page:The Zoologist, 4th series, vol 3 (1899).djvu/510

480 the 'Scientific American' there has recently appeared a memoir on "The Pearl-Button Industry of the Mississippi River," by Mr. Hugh M. Smith, of the U.S. Commission of Fish and Fisheries. The manufacture of buttons from the shells of native fresh-water Mussels began in the United States in 1891. Button-making has now become one of the principal businesses along a section of the Mississippi nearly two hundred miles in length. There are about four hundred species of Mussels found in the Mississippi River and its tributaries, but comparatively few are now utilized in or are adapted to button-making. We naturally find complaints as to the treatment of the "golden goose." "Not the least injurious feature of the fishery is the gathering of small Mussels for market, and the incidental destruction of small shells that are not utilized, but left on the banks or the ice to die." Mussels have many perils to surmount. "Animals which are known to prey on the Mussels are Muskrats, Minks, Raccoons, and Hogs, the first and last being especially destructive. The freshets to which the Mississippi is periodically subject undoubtedly do great damage to the Mussel-beds, burying them under sand and mud. Shifting sand-bars are also known to cover up beds. The fishermen sometimes find extensive beds of dead shells which appear to have been recently uncovered by the current. During freshets, when the stream finds new channels, many Mussels are carried from their beds, and left dry when the water subsides. Droughts are also liable to expose Mussel-beds, and cause much destruction. However, pollution of the water by refuse from cities and manufacturing establishments is perhaps the most serious menace to the Mussel-beds, next to the operations of the fishermen."