They are very small monkeys with relatively long tails. Males and females are of similar size. Their body being around 7-10 inches and weighing nearly 16 ounces. The fur of the marmoset is multicolored, being sprinkled with brown, grey, and yellow. Common marmosets have white ear tufts, while Penicillatas have black ear tufts and Geoffreys have a mostly white fur around their faces. A marmoset's face has black across the nose area and a white blaze on the forehead. The coats of infants lack ear tufts and have grey fur over their head and neck. Marmosets have claw-like nails on most of their fingers. Only their big toes have the flat nails. They can hang on to trees vertically and leap between them, as well as run across branches.