1. The relationship between C.R. length and weight of two series of foetuses from Grootfontein School of Agriculture, Cape Province, and Ermelo, Transvaal, is considered.
2. The thirteen foetuses used in Sex Physiology Study No. 13, which is part of the Grootfontein series, were employed to determine a relationship between weight and C.R. length along the curvature of the back.
3. It is suggested that for uniformity more attention be paid towards adopting a definite length measurement as a standard for studies in foetal growth.