A black stripe extends from the tail , along the dorsal midline to the head , where it forks at the top of the head in a distinguishing Y - shape leading to the dark rings around both eyes .
A black stripe sometimes extends down the snout .
A black stripe extends from the tail , along the dorsal midline to the head , where it forks at the top of the head in a distinguishing Y - shape leading to the dark rings around both eyes , and sometimes extends down the snout .