292 EXTINCT MONSTERS 
Glyptodonts seem to have been chiefly confined to the continent 
of South America, but some species are known to have extended 
their range as far as Mexico, and Texas into North America, A 
good deal of confusion has arisen with regard to the classification 
of these old-fashioned armadillos, on account of the fact that 
isolated specimens of their tails have often been found, and these 
cannot always be referred to the right carapaces. For example, it 
should be pointed out here that the tail represented in Plate LIII. 
really belongs to another genus, known as Hoplophorus.' 
In Glyptodon asper the scutes of the carapace had a beautiful 
rosette-like sculpture, while the sheath of the tail was entirely 
composed of a series of movable rings, ornamented with large 
projecting tubercles. The vertebra of the backbone are almost 
entirely fused together into a long tube, and also are joined to 
the under surface of the great shield, to which the ribs are 
united. The cheek-teeth are sixteen in number, four above and 
four below on each side. These are channelled with two broad 
and deep grooves, which divide the surface into three distinct 
lobes. Hence the name of the animal. 
Plate LII. represents Glyptodon clavipes (Owen) from the Pleis- 
tocene deposits of Buenos Ayres ; but the reader will gain a much 
better idea of the animal by inspecting the splendid specimen of 
Glyptodon asper in the Natural History Museum, near the centre 
window at the East end of the Gallery of fossil mammals. 
Plate LIII. is a restoration of another species by our artist.? 
In the Museum of the Royal College of Surgeons (which the 
reader is recommended to visit) there are several most valuable 
specimens of these extinct armadillos from South America. 
1 Greek—Hoplon, armour; phero, I bear. 
2 This plate is based on a beautiful drawing in a Spanish work, Anales del 
Museo publico de Buenos Aires. G. Burmeister, M.D., Phil. D, Tomo Segundo. 
