ANT-EATING. Ill 



acquired a special protection from their foes in the shaj)e 

 of a bony or scaly armour, which is a perfectly unique 

 feature in the whole mammalian class. Another peculiarity 

 of the group is that no less than three distinct sections of 

 its members — namely, the anteaters of South America, the 

 pangolins of southern Asia and Africa, and the African 

 aard-varks — have taken to feed mainly or exclusively on 

 termites, or so-called white ants. This practice obviously 

 gives them an advantage in the struggle of existence, since 

 with the exception of the marsupial banded anteater and 

 the egg-laying spiny anteater of Australia (with which, 

 of course, they do not come into competition), no other 

 mammals are in the habit of subsisting exclusively on 

 those insects. And we may notice here that of the three 

 groups of termite-eating edentates, two — namely, the ])an- 

 golins and the anteaters — are those which have entirely 

 lost their teeth ; while in the aard-varks those organs are 

 retained. As teeth are obviously of no sort of use to 

 animals subsisting on such a diet, we niay regard the two 

 former groups as those most specially modified for their 

 particular mode of existence ; and it may thus be suggested 

 that they have taken to termite-eating for a longer period 

 than the aard-varks. A similar observation also ajij^lies 

 to the banded and spiny anteaters of the antipodes, the 

 former retaining a nunaber of minute teeth, while in the 

 latter they have completely disappeared. Needless to say, 

 all termite- eating mammals, whether they be edentates, 

 marsupials, or egg-layers, have extremely long, nari-ow, 

 and extensile tongues with which to pick up their insect- 

 food ; but the presence of such an organ does not, of 

 course, imply any mutual affinities between the possessors 

 thereof, and is merely an instance of the similarity of 

 organs arising from adaptation to a simdar mode of 

 existence. The tongue of the aard-varks is, however, far 

 less elongated and extensile than that of the pangolins 

 and true anteaters ; and, therefore, tends to confirm our 

 euggestion as to the relative duration of time since the 

 ancestors of these creatures severally took to termite- 

 eatmg. Another instance of adaptation displayed by all 

 the edentates, except the arboreal sloths, is to be found in 



