In these large circular structures the beds stood against the wall and the single opening faced inward. These were described by Catlin and clearly indicated in his drawing of an interior of a lodge, plate 38, _a_. In Maximilian's work (p. 344) is a sketch of such a bed which shows it as a unit, not attached to the wall, and capable of being moved about. The sketch is reproduced in figure 7. These were so formed and inclosed in skins as to protect the occupants from the cold blasts of air which must have circulated about in the interior of the lodge during certain seasons of the year. And as additional protection "In the winter huts they place, at the inside of the door, a high screen of willow boughs, covered with hides, which keeps off the draught of air from without, and especially protects the fire." And Maximilian related how, about the middle of November or before, the Indians removed to their winter huts which were in a timbered area, and thus more protected from the winds and storms of winter. There they remained until the latter part of February, or the beginning of March, being governed by the climatic conditions. Thus about four months of the year would be spent in their winter village. As the greater part of their possessions would be deposited in underground caches they made frequent trips between their villages to get what was desired--food, clothing, skins, and other supplies. In the winter, when the frozen prairie was covered with ice and snow, they made use of sledges drawn by dogs to transport their goods from place to place. The sledges were "made of a couple of thin, narrow boards, nine or ten feet in length, fastened together with leather straps, and with four cross-pieces, by way of giving them firmness." [Illustration: FIG. 7.--Inclosed bed.]