96 MOSTLY MAMMALS 
of apertures for bristles, the same smoothness doubtless 
characterised the carapace. The head was protected by a 
smooth shield of small tesselated plates, and the skull was 
characterised by the peculiar twisting and curvature of 
the bones of the nose. 
Such are the chief characteristics of the better-known 
representatives of the mailed monsters of Argentina—a 
group which was continued in a straight line from the 
pigmy glyptcdon of Patagonia to the ring-tailed species of 
the Pampas, while all the other giant forms of the latter 
must be regarded as lateral offshoots from the original 
stock, which continued, as is so often the case, to develop 
more and more Sigarre characters until the date of their 
final disappearance. In conclusion, it should be added that 
a strange, gigantic armoured creature, found commonly in 
the cavern deposits of Brazil, and also rarely in Argentina, 
seems to have been a kind of connecting link between 
the glyptodons and the armadillos, having the carapace 
formed of a number of movable plates, arranged in a series 
of overlapping bands as in the latter, but with teeth of 
the type of the former. Unfortunately, however, this 
interesting creature, which must have been as big as a 
large rhinoceros, is known by such fragmentary remains 
that its full affinities cannot yet be determined, as we are 
still ignorant whether its skull approximated to the glypto- 
don or the armadillo type. 
Sufficiently protected from all attacks on the part of the 
wolf-like marsupials and such other large carnivorous 
mammals as may at the same period have roamed over 
Argentina, the pigmy glyptodon of the Santa Cruz beds of 
Patagonia could have had no difficulty in maintaining its 
existence against foes of all kinds, and subsequently giving 
rise to the gigantic mailed monsters described above. 
