Lastly, this wide prevalence and extreme tenacity of the tribal system may perhaps make it the more easy to understand the almost equally wide prevalence of that open-field system, by the simplest forms of which nomadic and pastoral tribes, forced by circumstances into a simple and common agriculture, have everywhere apparently provided themselves with corn. It is not the system of a single people or a single race, but, in its simplest form, a system belonging to the tribal stage of economic progress. And as that tribal stage may itself take a thousand years, as in Ireland, to wear itself out, so the open field system also may linger as long, adapting itself meanwhile to other economic conditions; in England becoming for centuries, under the manorial system, in a more complex form, the shell of serfdom, and leaving its _débris_ on the fields centuries after the stage of serfdom has been passed; in Ireland following the vicissitudes of a poor and wretched peasantry, whose tribal system, running its course till suddenly arrested under other and economically sadder phases than serfdom, leaves a people swarming on the subdivided [p245] land, with scattered patches of potato ground, held in 'run-rig' or 'rundale,' and clinging to the 'grazing' on the mountain side for their single cow or pig, with a pastoral and tribal instinct ingrained in their nature as the inheritance of a thousand years. Such in its main features seems to have been the tribal system as revealed by the earliest Irish and Welsh evidence taken together. There remains the question, What was the relation of this tribal system to the manorial system in the south-east of England and on the continent of Europe? III. THE DISTINCTION BETWEEN THE TRIBAL AND AGRICULTURAL ECONOMY OF THE WEST AND SOUTH-EAST OF BRITAIN WAS PRE-ROMAN, AND SO ALSO WAS THE OPEN-FIELD SYSTEM. «The south and east Britain not tribal but mainly agricultural before Saxon conquest.» The manorial system of the east and the tribal system of the west of Britain have now been traced back, in turn, upon British ground, as far as the direct evidence extends, _i.e._ to within a very few generations of the time of the Saxon conquest; and in neither system is any indication discernible of a recent origin. So far as the evidence has hitherto gone, the two systems were, and had long been, historically distinct. The tribal system probably once extended as far into Wessex as the eastern limits of the district long known as West Wales, _i.e._ as far east as Wiltshire; and within this district of England the manorial system was evidently imposed upon the conquered country, as it was later in portions of [p246] Wales, leaving only here and there, as we have found, small and mainly local survivals of the earlier tribal system. But no evidence has yet been adduced leading to the inference that before the Saxon invasion the Welsh tribal system extended all over Britain.