SOME EARLY MAMMALS 



255 



It is quite clear, then, that we cannot place the Dinoceras 

 in any order of living mammals. It is what palaeontologists call 

 a " generalised type ; " that is to say, it presents certain characters 

 seen in several groups of living quadrupeds, and not any of those 

 elaborated or highly developed parts which we see in such 

 animals to-day. Thus the proboscis of the elephant is the result 

 of great elongation of the cheeks and nose of its ancestor (see 



FIG. 95. Skull of Dinoceras mirabile, (After Marsh.) 



p. 269) ; in other words, the elephant is highly " specialised " in 

 that direction, whereas our Dinoceras had no proboscis, or only a 

 very slight one. 



Again, the six remarkable bony protuberances of the skull 

 served to some extent as horns, and probably were covered with 

 thick bosses of skin, and did not support true horns like those 

 of our modern oxen and other ruminants. Speaking of these 

 protuberances, Professor Marsh says, " None of the covering of 



