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,
Comb flounder Comb flounder The comb flounder, "Marleyella bicolorata", is a flatfish of the family Pleuronectidae. It is a demersal fish that lives on saltwater bottoms at depths of between . Its natural habitat is the tropical waters of the western Indian Ocean, from KwaZulu-Natal and Mozambique in Southern Africa, to coastal Tanzania and Kenya in the African Great lakes region, to Somalia in the Horn of Africa, to Karnataka and Maharashtra in India. It can grow up to in length. The comb flounder is a right-eyed flatfish. Its upper (eyed) side is dark brown, marked with vaguely cruciform dark spots and