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,
Orange-spotted trevally section being longer than the posterior straight section. The straight section of the lateral line has 14 to 26 scales followed by 20 to 30 scutes. The chest of the orange-spotted trevally is completely scaled, occasionally having a narrow naked region on the underside near the ventral fins. It has 24 vertebrae and 25 to 43 gill rakers. The orange-spotted trevally has a silvery grey- to brassy-coloured body, becoming paler to a silvery white ventrally. Many conspicuous orange to yellow spots occur on the sides of the fish, giving the species its name, and make for an easy way to