One warm day in winter, when some of the pussy-willows made a mistake and began to grow because they thought spring had come, a party of Muskrats were visiting in the marsh beside the pond. All around them were their winter houses, built of mud and coarse grasses. These homes looked like heaps of dried rushes, unless one went close to them. If one did that, he could plainly see what they were; and if one happened to be a Muskrat, and could dive and go into them through their watery doorways, he would find under the queer roof of each, a warm, dry room in which to pass the cold days.