In zoology, a quadruped of the genus Hystrix. The crested porcupine has a body about two feet in length, four toes on each of the fore feet, and five on each of the hind feet, a crested head, a short tail, and the upper lip divided like that of the hare. The body is covered with prickles which are very sharp, and some of them nine or ten inches long; these he can erect at pleasure. When attacked, he rolls his body into a round form, in which position the prickles are presented in every direction to the enemy. This species is a native of Africa and Asia.