202 EDENTATA 
approximate in structure to those of the next family, so that the 
genus tends to connect the Armadillos with the Glyptodonts. 
Family GLYPTODONTID. 
In the Pleistocene cavern-deposits of Brazil, but still more 
abundantly in the fluviatile deposits which cover the country in the 
neighbourhood of Buenos Ayres, are found the remains of some of the 
most remarkable forms of mammals yet discovered, the Glyptodonts, 
which may be regarded as forming a separate 
extinct family. They differ from the existing 
Dasypodide in their large size, and in having the 
carapace composed of a solid piece (formed by 
the union of a multitude of bony dermal scutes) 
without any movable rings, and in usually hav- 
ing also a ventral piece or plastron. The facial 
portion of the skull is very short. <A long 
process of the maxillary bone descends from 
the anterior part of the zygomatic arch. The 
ascending ramus of the mandible is remarkably 
high. The teeth are 8 in the known species, 
all much alike, having two deep grooves or 
flutings on each side, so as to divide them into 
three nearly distinct lobes (Fig. 68). The verte- 
bral column is almost entirely ankylosed into 
a solid tube, and there is a complex joint at the 
base of the neck, to allow of the head being 
retracted within the carapace. The limbs are 
very strong, and the feet short and _ broad, 
resembling externally those of an elephant or 
tortoise. This family is mainly characteristic 
of the southern half of the American continent, 
but some species of the type genus ranged into 
Fic. 68.—Tooth of Glyp, Texas and Mexico. Many species of the family 
todon from the side, and have been described and figured, especially by 
aoe surface. Burmeister Gn the fnnles del Museo publica de 
Buenos Aires), among which the following may 
be noticed. Hoplophorus is characterised by the sculptured and 
frequently thin scutes of the carapace, those of the periphery being 
flat, and not raised into prominences. The caudal sheath has 
several overlapping movable rings at the base, and ends in a lone 
subcylindrical terminal tube similar to the one represented with the 
carapace of Gilyptodon in Fig. 69, which in all probability really belongs 
to the genus under consideration. Each foot has four complete 
digits, and the humerus has an entepicondylar foramen. Most of the 
