[The length growth of the north sea sole (Solea vulgaris Quensel) and the problem of annual variations (author's transl)].

In spite of the small number of 8 averaged length values for the North Sea sole nonlinear regressions yield remarkable results for 18 out of 21 functions of organic growth. Functions implying finite growth times give rise to the assumption that length growth of Solea vulgaris theoretically comes to rest between 20 1/2 and 23 years of age. Taking up early experiences by Bückman (1934) detailed considerations are given to annual variations of growth. For this purpose the gained functions are modified to the cases of reduced or stagnating development in low temperatures.