[Approximations of weight increase of the male and female Rattus norvegicus using Calhoun's (1952) data].

After a short review on weight series of rats and their approximation by rather different growth functions data from Calhoun (1952) are submitted to thorough investigations applying 14 functions altogether, 4 of which yield a definite growth time. The results for the best approximations are complied for the male and female in 2 tables together with the parameters as gained by nonlinear regressions and characteristic data of rat growth.