96 MAMMALIAN DESCENT. [LECT. IV. 



and there larger hairs are seen, but these fail to 

 reach the surface, turning again towards the inside, 

 like nails driven into wood that is too hard for their 

 points. 



Nothing could be more distressing and disgusting to 

 the highest type that wears a covering of hair than this 

 matting together of these fine, delicate filaments that 

 in their rich fulness crown the head of Beauty : when it 

 does occur it is abnormal, and is relegated to pathology. 

 But here, in the Pangolin, we see a perfect coat of mail 

 formed by the imbrication of these large tracts of well- 

 cemented hair-plates. Such an armour would, if the sun 

 were overhead, " scald with safety ;" but the Pangolin is 

 a lover of the shade, and, although not very intelligent, 

 is much too wise to allow himself to be burnt under his 

 own roof-tiles. 



The other Old World Edentate the Aard-vark (Oryc- 

 teropus) is not covered with armour, but with a thick coat 

 of coarse hair. He is not truly edentate, but has teeth 

 similar to those of the Armadillo. Similar, but not the 

 same, for his sub-cylindrical rootless teeth have many 

 vertical pulps instead of one. A section of these shows 

 a compacted mass of hexagonal prisms ; so that his 

 teeth might be said to be a sort of ivory whalebone. 



Most biologists think that these are a degradation 

 of proper mammalian teeth. Long ago, Professor 

 Owen, in his magnificent Odontogmphy, showed that 

 the various sorts of Cartilaginous fishes have teeth 



