90 Dr. Burmeister on the Species of Glyptodon 
and the more or less important remains of five more individuals; 
amongst which we have met with some specific differences from 
the two principal species from the soil of Buenos Ayres. Let us 
first describe the skeleton in general. i 
The skull is very thick, and, comparing it with the acute skulls 
of existing Armadillos, is very short and obtuse. The nasal bone, 
the forehead, and the vertex being in the same plane with the 
occiput, form a flat surface of 11 inches in length by 54 in width 
between the eyes. This short figure depends principally on the 
shape of the nasal bone, which is so short that the point of the 
lower mandible by far surpasses that of the upper, which latter 
was in this animal much longer in the living state, as there then 
existed a broad and strong cartilage in this organ somewhat pro- 
minent from the head. It is probable that the living animal might 
have had a thick and strong snout, to grub up the earth, and 
seek its food in this manner, as the Armadillos do at present. 
It is not very evident up to what point the cranial bones ex- 
tended, from the want of sutures of the skull, since it is entirely 
in one piece, and destitute of any suture, without any vestige of 
the primitive bones of the young animal. Neither can the frontal 
bones be distinguished from those of the vertex nor from those 
of the occiput, because they are all united in one capsule. The 
perpendicular part of the occiput is very low, and the foramen 
occipitale is of a transversely elliptical shape, which is not met 
with in any other mammal. The internal cavity of the cranium 
is of a surprising smallness, as was also the brain; and these 
characters indicate that this was an animal exceedingly stupid 
and sluggish—qualities which are also indicated by the size of 
the lower mandible and the great extent of its grinding-portion. 
There is no other animal which has so descending a palate 
(ste in orig.) nor such projecting teeth as the Glyptodon. Above 
all, the ascending ramus of the inferior mandible is very high, 
in such a proportion that no animal equals it in this respect. 
The anterior inclination of this ramus, which forms with the 
horizontal ramus an angle smaller than a rectangle, is a character 
peculiar to the Glyptodon; and this inclination indicates a 
powerful grinding-apparatus, which surpasses that of other 
Mammalia, even that of the Elephant. The symphysis is pro- 
duced, like the spout of a jug (la boca de un.cdntaro), this part 
being toothless ; there are eight teeth on each side of the inferior 
and superior mandibles, more or less alike in form; but those 
of the upper mandible are a little larger, and those of the fore 
part of each jaw slightly narrower. 
Each tooth is formed by the conjunction of three rhombic 
prisms, which have on each side deep excavations between the 
prominent points of the three prisms. This form may be com- 
