LECT. IV.] THE EXTINCT GLYPTODON. 95 



lost relative, the Glyptodon. These forms, with their 

 bony cases, horn-covered, are not such strange members 

 of the Mammalian class, to my mind, as the Pangolins, 

 with their merely horny, imbricated scales. At first 

 sight, we seem to have in these old-world Edentata 

 types that have relapsed into a reptilian condition ; they 

 are, however, merely mimetic of the scaly tribes. The 

 Armadillos come nearest to the Keptiles, such as the 

 Blind-Worm, the Tortoise, and the Crocodile, whose 



FIG. 11. Embryo (one-third ripe) of a Pangolin (Manis sp.), 

 reduced to f natural size. 



b<5ny scales are encased in horn, but none of them fail 

 to develop at every available place, that glory of the 

 Mammal the hair. But the Pangolin is tiled over 

 with patches of cemented hair. In the early embryo, 

 lozenge-shaped tracts of skin are seen all over its body, 

 with lines of thinner cuticle between. 



Under the microscope, sections of these thicker tracts 

 show that they are composed of fine hairs cemented 

 together by a copious growth of epidermic cells ; here 



