Age determination in fish fish. Johannes Reibisch, working for the Commission of Scientific Investigation of German Seas at Kiel, attempted to use Hoffbauer’s techniques to age plaice ("Plueronectes platessa") but found it difficult to accurately discern annuli. He decided to study a different structure and in 1899 he published the first procedures using otoliths as an aging structure. A fellow scientist also with the German Commission at Kiel, Friedriche Heincke, also frustrated with difficult scale annuli, further studied other structures to age fish. He discovered annuli in the vertebrae, opercula, and pectoral girdle and published his findings in Heicke 1905. The works of Hoffbauer,
Elassoma evergladei 115 to 500, increasing with the fish's size. The fish has variable color and form. Its body is generally colored brown with darker spots. The fish has several rows of dark red spots on its dorsal and anal fins. "Nonbreeding" fish may have light streaks, mottling, or blotches. Females of the species in general are colored brown on their backs with mottled brown and cream/white coloring underneath, or they may be reddish brown. The females have no markings. "Breeding" males are colored black with iridescent blue spots. Males have black fins with or without brown spots. Male bodies may be