Although a large, active dog, the Collie is both elegant and graceful, appearing to float over the ground as it runs. Loyal and affectionate, the breed is naturally responsive to humans. Marked characteristics include the beautiful coat of the rough variety and the breedapos;s lean wedge-shaped head. The coat can be rough or smooth and the four accepted colors are sable and white, tri-color, blue merle and white. The best-known Collie is, of course, the famous Lassie.