=The Agricultural Stage.=--The growing and storage of crops, increased by the use of animal power, greatly changed the economic and social conditions of man. It made possible and profitable the living in fixed habitations, even in communities, and this brought out the needs of rules of government. But even yet each family provided without the assistance of others for practically all its own needs. In planting, reaping, threshing, grinding the meal and cooking, the family became the unit. No great division of labor was yet evident, consequently exchange, barter, and transportation still remained low. Ownership of land was necessary if a family was to cultivate the same land year after year. This meant definite rules and laws and consequently the development of governments. Ownership of herds and land brought wealth and a certain distinction in the community. Slavery, which had no doubt existed to some extent in the pastoral stage, here, because it greatly increased wealth, grew immensely. Large families likewise meant more workmen and greater wealth, distinction, and leisure, hence polygamy and polyandry often existed. As the evolution continued there was a trend toward handicraft and the division of labor; the products of one place began to be exchanged for the products of other places. This necessitated some forms of transportation, meager though they might be, and trails between communities. =The Manorial and Feudal Systems.=--In England and on the continent during the later years of this stage there were developed the manorial or feudal forms of government. The people lived largely in villages each controlled by a lord or earl (eorl) and to whom in return for his protection, the use of land, and other favors, they were bound to return to him service in the cultivation of his land and in waging war when called upon to do so. The lords in turn held their allegiance to the king. Some handicraftsmen were among the retainers but they were so few that they did not form an important part of the village, neither was there a great deal of travel or transportation. The manor instead of the family was the unit, and it was almost self-sufficient. The land was allotted in small tracts and tilled in the manner designated by the lord. Each person raised barley, oats, peas, and lentils sufficient for his own needs. Variation in crops was little practiced. Much land at distances from the manor was still devoted to herds and flocks.