MACILE'RODUS, a genus of extinct carnivorus animals of the feline or cat family, presenting the most specialized example of the carnivorous type known. The upper canines have a most extraordinary develobment, being long, saber-shaped, with finely seiTated margins. The upper jaw has no true molars, and in the under jaw the premo lars are reduced to 2 on each side. The dental formula is . 3 -3 1-1 2-2 0- 0 = 26.
3-3 ' 1-1 ' 2-2 0-0 These formidable flesh-caters are called " saber-toothed tigers," but some of the species resembled the lion, and are spoken of as lions by some authorities; and were fully the size of the largest of the present fe/is /en. They had a wide distribution in space and time, their fossils being found iu Great Britain, in various parts of the continent of Europe, in India and other parts of Asia, aud Norbh and South America, ranging in gine from the miocene formation to the middle of the quaternary, or human age. The bones of macharodus prill241,213, from the 13ad Lands of Dakota]] indicate an animal some what snuffler than the American panther; with smaller cranium and orbit, and also described as differing in dental formula from that given above, having 3 upper incisors, and 3 upper premolars on each side instead of 2, making in all 30 teeth instead of 26. There is another 'larger species from the same locality, but with less
perfect rfmains. cultridens, from the tertiary of the Val d'Arno is of large size, having upper canines 81 in. along the anterior curve, while M. neogferts; from quaternary caverns of Brazil was still larger, having upper canines projecting 8 in. beyond their sockets. The bones of these animals are often found along with those of several species of quadrumana, and of mammoth deer, hears, horses, elephants, and also various others of their own family, as hyenas, deers, and extinct lions; in fact, they flourished in the age of mammals, and must have made sad havoc among the more defenseless animals.