. Animals of the past, an account of some of the creatures of the ancient world. thetrue elephants, of which the mammoth is anexample, in the structure of the teeth. In themastodons the crown, or grinding face ofthe tooth, is formed by more or less regulary\-shaped cross ridges, covered with enamel,while in the elephants the enamel takes theform of narrow, pocket-shaped plates, set up-right in the body of the tooth. Moreover, inthe mastodons the roots of the teeth are longprongs, while in the elephants the roots aresmall and irregular. A glance at the cuts willshow these distinctions better th
. Animals of the past, an account of some of the creatures of the ancient world. thetrue elephants, of which the mammoth is anexample, in the structure of the teeth. In themastodons the crown, or grinding face ofthe tooth, is formed by more or less regulary\-shaped cross ridges, covered with enamel,while in the elephants the enamel takes theform of narrow, pocket-shaped plates, set up-right in the body of the tooth. Moreover, inthe mastodons the roots of the teeth are longprongs, while in the elephants the roots aresmall and irregular. A glance at the cuts willshow these distinctions better than they canbe explained by words. Back in the past, how-ever, we meet, as we should if there is any truth 198 THE MASTODON 199 in the theory of evolution, with elephants hav-ing an intermediate pattern of teeth. There is usually, or at least often, anotherpoint of difference between elephants and mas-todons, for many of the latter not only hadtusks in the upper, but in the lower jaw, andthese are never found in any of the true ele-phants. The lower tusks are longer and larger. Fig. 38. — Tooth of Mastodon and of Mammoth. in the earlier spepies of mastodon than inthose of more recent age and in the latest spe-cies, the common American mastodon, the lit-tle lower tusks were usually shed early in afford some hints of the relationships ofthe mastodon; for in Europe are found re-mains of a huge beast well called Dinotheri-um, or terrible animal, which possessed lowertusks only, and these, instead of sticking out 200 ANIMALS OF THE PAST from the jaw are bent directly perfect skull of this creature has yet beenfound, but it is beUeved to have had a shorttrunk. For a long time nothing but the skullwas known, and some naturalists thought theanimal to have been a gigantic manatee, or seacow, and that the tusks were used for tearingfood from the bottom of rivers and for anchor-ing the animal to the bank, just as the walrususes his tusks for digging clams and clim
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectpaleontology, bookyea
