All furs are best in winter. There is a period from the beginning of Spring to the middle of September, when furs are worthless. The reason why furs become worthless in summer is, that all fur-bearing animals shed their coats, or at least lose the finest and thickest part of their fur as warm weather approaches, and have a new growth of it in the fall to protect them in winter. This whole process is indicated in some animals, by the color of the inside part of the skin. As summer approaches, it becomes brown and dark. That is a sign that the best fur is gone. The dark skin absorbs heat in place of the thick undercoat that has shed. Afterward the skin grows light-colored again and in winter when the fur is in the best condition, it is altogether white. When the pelt is white, it is called prime by the fur-dealers. The fur is then glossy, thick and of the richest color and become prime about the first of November. There is probably some variation with the latitude, of the exact period at which furs become prime, the more northern being a little in advance. Some fur takers begin too early in the season, consequently much poor fur is taken, which must be sold at low prices, and is unprofitable to the hunter, the fur-buyer, and the manufacturer.