Skin a mammal as soon after death as possible. Lay mammal on back and with scissors or scalpel open the skin along belly from about midway between fore and hind legs to vent, taking care not to cut muscles of abdomen. Skin down on either side of the body by working the skin from flesh with fingers till hind legs appear. Use corn-meal to stanch blood or moisture. With left hand grasp a leg and work the knee from without into the opening just made; cut the bone at the knee, skin leg to heel and clean meat off the bone (leaving it attached of course to foot). In animals larger than squirrels skin down to tips of toes. Do the same with other leg. Skin around base of tail till the skin is free all around so that a grip can be secured on body; then with thumb and forefinger hold the skin tight at base of tail and slowly pull out the tail. In small mammals this can be done readily, but in foxes it is often necessary to split the skin up along the under side and dissect it off the tail-bones. After the tail is free skin down the body, using the fingers (except in large mammals) till the fore legs are reached; treat the fore legs in the same manner as hind legs, thrusting elbow out of the skin much as a person would do in taking off a coat; cut bone at elbow; clean fore-arm bone. Skin over neck to base of ears. With scalpel cut through ears close to skull. With scalpel dissect off skin over the head (taking care not to injure eyelids) down to tip of nose, severing its cartilage and hence freeing skin from body. Sew mouth by passing needle through under lip and then across through two sides of the upper lip; draw taut and tie thread. Poison skin thoroughly. Turn skin right side out. Next sever the skull carefully from body, just where the last neck-vertebra joins the back of the skull. It is necessary to keep the skull, because characters of bone and teeth are much used in classification. Remove superfluous meat from the skull and take out brain with a little spoon made of a piece of wire with loop at end. Tag the skull with a number corresponding to that on skin, and hang up to dry. A finished specimen skull is made by boiling it a short time and picking the meat off with forceps, further cleaning it with an old tooth-brush, when it is placed in the sun to bleach. Care must be taken always not to injure bones or dislodge teeth.