MISSING LINKS 



is thus seen. Orycteropus feeds upon ants and it is said 

 to impatiently thump with its heavy tail before com- 

 mencing operations upon an ant hill ; this throws the 

 small inhabitants into such a panic that they run 

 hither and thither in their confusion and pour out into 

 the jaws of their foe. As it feeds on ants it is not sur- 

 prising to find that Orycteropus has a particularly long 

 and viscid tongue like the tongue of other formicivorous 

 creatures. It is surprising, however, to find in its 

 mouth, besides a long tongue, an extensive range of 

 teeth. Other ant-eating creatures, for instance the 

 anteater, have no teeth. One is disposed to wonder 

 if this unexpected array of teeth is not an inheritance 

 from the not very remote days when the Orycteropus, 

 so to speak, chewed the cud like an ox. The mystery 

 of its origin is one upon which but little light has been 

 thrown. While the discovery of numerous fossil links 

 bind together other groups of mammals, no such con- 

 nexions are forthcoming in the case of our aard vark. 

 It is an isolated and friendless type declining to be 

 allied even to its neighbour, the Manis or pangolin. 

 The old idea that it came near to the ant-eater of America 

 has long since been exploded. Probably it is not an 

 exaggeration to say that no two mammals are further 

 apart than these two. The only hints that we seem 

 able to get are in the brain. The nervous system 

 generally among animals is an exceedingly conserva- 

 tive system, changing but slightly with other changes, 

 and then showing up unexpected likenesses in beasts 

 apparently remote. It has been pointed out that the 

 brain of the Orycteropus is singularly like that of an 

 ungulate animal ; and it is perhaps to these creatures 

 that Orycteropus shows the most likeness. In the 

 meantime there are at least two distinct species of 

 aard vark found in Africa, a northern and a southern 

 form, while in former times, as shown by its fossil 



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