The following chapters are in a certain sense executing a bequest. It was no less a man than Karl Marx who had reserved to himself the privilege of displaying the results of Morgan's investigations in connection with his own materialistic conception of history which I might call ours within certain limits. He wished thus to elucidate the full meaning of this conception. For in America Morgan had in a manner discovered anew the materialistic conception of history originated by Marx forty years ago. In comparing barbarism and civilization he had arrived in the main at the same results as Marx. And just as "Capital" was zealously plagiarized and persistently passed over in silence by the professional economists in Germany so Morgan's "Ancient Society" was treated by the spokesmen of "prehistoric" science in England.My work can offer only a meager substitute for that which my departed friend was not destined to accomplish. But in his copious extracts from Morgan I have critical notes which I here with reproduce as fully as feasible.