_The tusk obtained by Mr. Beach and mentioned in the text still holds the record for mammoth tusks. The greatest development of tusks occurred in Elephas ganesa, a species found in Pliocene deposits of the Siwalik Hills, India. This species appears not to have exceeded the existing elephant in bulk, but the tusks are twelve feet nine inches long, and two feet two inches in circumference. How the animal ever carried them is a mystery, both on account of their size and their enormous leverage. As for teeth, an upper grinder of Elephas columbi in the United States National Museum is ten and one-half inches high, nine inches wide, the grinding face being eight by five inches. This tooth, which is unusually perfect, retaining the outer covering of cement, came from Afton, Indian Territory, and weighs a little over fifteen pounds. The lower tooth, shown in Fig. 38, is twelve inches long, and the grinding face is nine by three and one-half inches; this is also from Elephas columbi. Grinders of the Northern Mammoth are smaller, and the plates of enamel thinner, and closer to one another. Mr. F. E. Andrews, of Gunsight, Texas, reports having found a femur, or thigh-bone five feet four inches long, and a humerus measuring four feet three inches, these being the largest bones on record indicating an animal fourteen feet high._ _There is a vast amount of literature relating to the mammoth, some of it very untrustworthy. A list of all discoveries of specimens in the flesh is given by Nordenskiold in "The Voyage of the Vega" and "The Mammoth and the Flood" by Sir Henry Howorth, is a mine of information. Mr. Townsend's "Alaska Live-Mammoth Story" may be found in "Forest and Stream" for August 14, 1897._ [Illustration: Fig. 37.--The Mammoth as Engraved by a Primitive Artist on a Piece of Mammoth Tusk.] XI THE MASTODON "_... who shall place A limit to the giant's unchained strength?_" The name mastodon is given to a number of species of fossil elephants differing from the true elephants, of which the mammoth is an example, in the structure of the teeth. In the mastodons the crown, or grinding face of the tooth, is formed by more or less regular /\-shaped cross ridges, covered with enamel, while in the elephants the enamel takes the form of narrow, pocket-shaped plates, set upright in the body of the tooth. Moreover, in the mastodons the roots of the teeth are long prongs, while in the elephants the roots are small and irregular. A glance at the cuts will show these distinctions better than they can be explained by words. Back in the past, however, we meet, as we should if there is any truth in the theory of evolution, with elephants having an intermediate pattern of teeth. [Illustration: Fig. 38.--Tooth of Mastodon and of Mammoth.]