The two main customs which governed the descent of villeins` tenements and prevailed in medieval England were the customs of partible and impartible inheritance. According to the custom of impartible inheritance, a villein`s holding went at his death to only one of his sons. The inheritance custom of some manors was that only the eldest son could inherit, that was promogeniture, and the custom of others was that only the youngest son could inherit-the Borough English. In any case, only one of his sons could inherit. On the other hand, by the custom of partible inheritance, a villein`s holdings were equally divided among his sons at his death. Of the customs of partible inheritance, the most prominent was that of gavelkind, which was the custom of Kent. The traditional explanation of the inheritance customs in medieval England is that the central England was marked by impartible inheritance and open-field. and Kent and East Anglia by customs of the partible and non-open field. However, for the theorists who are in favor of the partible inheitance customs, it does not seem to be true that the areas of partible inheritance and open-field farming are incompatible, nor that partible inheritance is confined to Kent and East Anglia. They have, Therefore, asserted that even in some parts of open-field area, the coparcenary was a general feature, composition of holdings was being constantly altered and partible inheritance was widespread. But it was more likely that impartible ingeritance tended to occur, not universally but statistically, in the open-field area of England and partible inheritance in non-open-field areas both to the east and to the west of the open field belt. In so far as customary tenements were concerned, the impartible inheritance customs, such as primogrniture and Borough English, was unquestionably the rule in the relevant parts of England in the twelfth and thirteenth century. The balance of probabilities seems to be even more strongly in favor of the view that the open-field system, rather than the system of cultivation in severalty, was the dominant form of arale cultivation at the time.