[Weight growth of the tunny (Thunnus thynnus) as a function of time and length]

Weight growth according to the dates of SELLA (1929) was first investigated by Krüger (1973) with the Gompertz-, Bertalanffy- and Reciprocal Function. Results showed significant differences due to the lack of values after 14 years of the tunny's development. In this contribution the work of Krüger is carried on based on a much broader scale of growth functions with infinite or restricted time of weight increase. Moreover relations between the length and original and modified weights are established giving results seldom obtained in such unity with other species.