CHORDATA — VERTEBRATA — xMAMMALS 383 



itf 



Fig 164. — Outline restorations of some of the more characteristic mammals living 

 in North America during- the Ice age (Pleistocene). These are reduced to a uni- 

 form scale, with a pointer dog (in the frame) to show relati\e sizes. Note the 

 difference in size betw^een these and the Eocene mammals (Fig. 163). i. The Co- 

 lumbian elephant {Elephas columbi). 2. The giant ground-sloth {Megalonyx 

 jefersoni), an edentate. 3. Stag-moose (Cervalces scotli), one of the artiodactyl 

 ungulates. 4. The American mastodon (Mammut americanum) . 5. The giant 

 h&diWtx {Castoroides ohioensis), a. rodent. 6. T txdiS \\ors& {Equus scotti). 7. Saber- 

 tooth tiger {Smilodon calijornicus). (From Scott.) 



