THE ANCESTORS OF ELEPHANTS 



and some far away in the fine Museum of the 

 Egyptian Survey in Cairo. In Fig. 86 a 

 drawing (No. 4) is given of the skull of 

 this Palaeomastodon. The figure includes 

 several other elephant forms. We have the 

 skull and lower jaw of Tetrabelodon (No. 3), 

 of the American mastodon (No. 2), and of the 

 Indian elephant (No. 1). It will be seen at 

 once how completely the Palaeomastodon skull 

 fills in the series leading back from the bull- 

 dog-faced elephants with short jaws to or- 

 dinary mammals. It has a fairly long skull 

 and long bony face, with two large — but not 

 very large — downwardly directed tusks. The 

 jaws are long, but the lower one not so exces- 

 sively long as that of Tetrabelodon (No. 3), 

 and the cheek-teeth are there in nearly full 

 number — as many as five in each half of each 

 jaw. These are well seen in the view of the 

 lower jaw given in Fig. 87 (No. 2), where the 

 condition of the lower jaw of Palaeomastodon is 

 clearly contrasted with that of Tetrabelodon 

 {Mastodon angustidens, No. 3). 



In Palaeomastodon we have arrived, by 

 passing as far back as the Eocene strata, at an 

 ancestral elephant-like creature which serves 



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