A Biograph release, reportedly D. W. Griffith's experimental animated monster movie, whose working title was Wars of the Primal Tribes. According to Roy Kinnard, Beasts and Behemoths: Prehistoric Creatures in the Movies (Metuchen, NJ: Scarecrow Press, 1988), D.W. Griffith made for Biograph a previous film, Man's Genesis (1912), about a cave-dwelling couple. It had no prehistoric creatures in it, but was successful enough to warrant a 20-minute sequel, The Primitive Man (1913), also known as Brute Force and Wars of Primal Tribes. (I think I remember reading elsewhere that this is partly explained by British vs. American releases; I also think I remember reading elsewhere that these films are lost.) "The first half of The Primitive Man simply reused all the footage from Man's Genesis . . . but the second reel . . . exhibited what may be the screen's first dinosaurs -- stiff, mechanical, life-sized mock-ups and enlarged reptiles" (1).