A mask on a dog is a darkened area, often on the face, from where it gets its name. Masks only occur on dogs that have eumelanin(dark) in their coats.It can occur with solid dark colours, dark patterned dark coats and also with mixed dark/light coats. A mask will not be obvious on a dog that is otherwise solidly dark coloured although it may be present. Masks are most noticeable on sable and brindle dogs. The presence or absence of a mask is dependent on the E gene where [ E m ] gives a mask and [ E ] does not. A mask, if present, can range from a simple darkened muzzle to a raccoon-type eye mask to a full dark face extending into the ears. A dark dorsal stripe is common and some masked dogs also have a dark tail and dark paws.
NEXT ... points of confusion - point patterns