An investigation of the food chains leading to the production of Florida spotted gar, Lepisosteus platyrhincus DeKay, was conducted in a 3-mile section of the Tamiami Canal approximately 20 miles west of Miami. In this area these fish are extremely abundant, and those collected ranged in length from 10.5 to 24.4 inches. Collections of gar, forage fish, plankton, periphyton, bottom fauna, and physicochemical data were obtained at frequent intervals from February 20 to June 28, 1952. A total of 448 gar stomachs was examined, of which only 106 (23.7 percent) contained food. Stomachs of 572 specimens of fish, representing 9 species known to serve as food for gar, were obtained and the contents analyzed. Stomachs of fresh-water shrimp, Palaemonetes paludosa, and other invertebrates which entered into the food chains were examined.