«Analogy of the _jugum_ and _centuria_ to the yard-land and hide.» We have also seen that the twenty-five or thirty jugera of the single yoke were probably fixed as an eighth of the Roman _centuria_, as the yard-land was the eighth of a double hide. The common acreage of the centuria was, as we have seen, 200 or 240 jugera. The latter number may be the simple result of the use of the long hundred of 120; or it may have resulted, as suggested above, from the necessity of making the centuria of the free citizen's typical estate divisible into four double holdings of 60 acres, or eight single holdings of 30 acres each. Be this as it may, the centuria, or typical estate of a free citizen in a regularly constructed Roman colony, seems to have stood to the single or double holding of the common and often semi-servile settler in the same arithmetical relation as the Saxon larger hide of 240 acres did to the yard-land.[426] We have, then, two kinds of holdings:-- 1. The one or more _centuriæ_ embraced in the [p293] latifundia or villas of the large landowners, which, however, when tilled by their coloni, and not by slaves, might well be subdivided into holdings of sixty or thirty acres each. 2. The double and single holdings of the smaller settlers on the 'ager publicus' of fifty or sixty and twenty-five or thirty acres each. And we may conclude that the system of taxation called the '_jugatio_' was founded upon these facts, though in order to equalise its burden the assessment of an estate or a territory in juga became, under Diocletian, a hypothetical assessment, corresponding no longer with the _actual_ number of yokes, just as the Saxon hide _ad geldam_, at the date of the Domesday Survey, no longer corresponded with the actual carucate _ad arandum_. Another resemblance between the Roman jugation and the Saxon hidage was to be found in the method adopted when it became needful to reduce the taxation of a district. Thus, the land of the Ædui had been ravaged and depopulated. It had paid the tributum on 32,000 juga; 7,000 juga were released from taxation. In future it was assessed at 25,000 juga only; and so relief was granted.[427] «The _tributum_ paid by the lord, who claimed tribute from his tenants, or '_tributarii_.'» Further, as the English manorial lord paid the hidage for the whole manor, so the lord of the villa, under Roman law, paid the tributum not only for his own demesne land, but also for the land of his coloni and tenants. Just as the servile tenants of a Saxon thane were called his '_gafol gelders_,' so the [p294] semi-servile tenants of a Roman lord were called his _tributarii_. In both cases they paid their tribute to their lord, whilst the lord paid the imperial tributum for himself and for them.[428] «_Coloni_ and _tributarii_ in Britain.» In a decree of the year 319, issued by Constantine to the 'Vicar of Britain,' words are used which prove that there were _coloni_ and _tributarii_[429] on British estates.[430]