Now, as in the surveys the family groups or gwelys were located so as to occupy sometimes several villatæ, and sometimes undivided shares in villatæ along with others, so, if we may take the villata of the surveys as equivalent to the tref or maenol of the Codes, we must expect to find that the kindreds of tribesmen at the period of the Codes were scattered in the same way over the trefs and maenols. And, as the maenol was a group of trefs, the _tref_ is the unit of tribal occupation as to which a clear understanding is most necessary. In this, however, we may be, after all, only partly successful. The word _tref_, though generally used for a homestead or hamlet, seems from its other meanings to involve the idea of a _group_. [Sidenote: The tref and its ‘randirs.’] There were cases in which a disputed matter of fact had to be established upon the evidence of men of the _gorvotref_, _i.e._ by men of the groups outside the tref in which the question in dispute arose.[30] And this _gorvotref_ was not merely the next adjoining tref or trefs, but it consisted of those _randirs_ or divisions of neighbouring trefs of uchelwrs, or tribesmen, whose boundaries touched the tref in which the disputed facts arose. Neighbouring randirs of taeog trefs, _i.e._ the trefs of non-tribesmen, were excluded, presumably because the testimony of taeogs in matters relating to tribesmen was not relied on. But this compound of the word tref implies that its general sense was a group of homesteads. That, in general, trefs had defined boundaries, is clear from the fact that it was an offence to break them, and this applied also to the randirs or divisions of the tref.[31] [Sidenote: The trefgordd of one herd and one plough.] Speaking, then, of the group generally known as a tref, we must regard it, not only as a taxable area, but also as the natural group known everywhere as a _trefgordd_, _i.e._ the natural group of the homesteads of relatives or neighbours acting together as a single community as regards their cattle and their ploughing. The typical lawful _trefgordd_ is thus described:-- This is the complement of a lawful _trefgordd_: nine houses and one plough and one oven (odyn) and one churn (_gordd_) and one cat and one cock and one bull and one herdsman.[32] There is another passage which mentions the nine buildings in the tref. These persons do not forfeit life.… The necessitous for the theft of food after he has traversed three trevs, and nine houses in each trev, without obtaining a gift though asked for.[33]