What is one of a mongrel breed of dogs said to have been a cross between the sheep dog, greyhound, and spaniel. It hunts game silently, by scent, and is often used by poachers called?

lurcher — (Zoöl.) One of a mongrel breed of dogs said to have been a cross between the sheep dog, greyhound, and spaniel. It hunts game silently, by scent, and is often used by poachers. (Webster's 1913.)

Sources