The head imparts to the Boxer a unique individual stamp peculiar to the breed. It must be in perfect proportion to his body; above all it must never be too light. The muzzle is the most distinctive feature. The greatest value is to be placed on its being of correct form and in absolute proportion to the skull. The beauty of the head depends upon the harmonious proportion between the muzzle and the skull. From whatever direction the head is viewed, whether from the front, from the top or from the side, the muzzle should always appear in correct relationship to the skull. That means that the head should never appear too small or too large. The length of the muzzle to the whole of the head should be as 1 is to 3. The head should not show deep wrinkles. Normally wrinkles will spring up on the top of the skull when the dog is alert. Folds are always indicated from the root of the nose running downwards on both sides of the muzzle. The dark mask is confined to the muzzle. It must be in distinct relief to the colour of the head so that the face will not have a "sombre" expression. The muzzle must be powerfully developed in length, in breadth and in height. It must not be pointed or narrow, short or shallow. Its shape is influenced through the formation of both jaw-bones, the placement of teeth in the jaw-bones, and through the quality of the lips. The top of the skull should be slightly arched. It should not be so short that it is rotund, too flat, or too broad. The occiput should not be too pronounced. The forehead should form a distinct stop with the top line of the muzzle, which should not be forced back into the forehead like that of a Bulldog. Neither should it slope away (downfaced). The tip of the nose should lie somewhat higher than the root of the muzzle. The forehead should show a suggestion of furrow which, however, should never be too deep, especially between the eyes. Corresponding with the powerful set of teeth, the cheeks accordingly should be well developed without protruding from the head with "too bulgy" an appearance. For preference they should taper into the muzzle in a slight, graceful curve. The nose should be broad and black, very slightly turned up. The nostrils should be broad with a naso-labial line between them. The two jaw-bones should not terminate in a normal perpendicular level in the front but the lower jaw should protrude beyond the upper jaw and bend slightly upwards. The Boxer is normally undershot. The upper jaw should be broad where attached to the skull, and maintain this breadth except for a very slight tapering to the front.