212 
the occipital condyles are portions of cylinders, placed horizontally, 
each in a line with the paroccipital process ; the precondyloid foramen 
is placed close to the condyle ; the supra-occipital bone is broad above, 
forming on each side a strong thickened ridge; the lower jaw is 
narrowed and slenderly produced anteriorly. 
The true affinities existing among the various Armadilloes have 
been rightly perceived by the Baron Cuvier, and are well pointed out 
in the ‘Ossemens Fossiles’ ; but he did not designate the subgenera 
by any particular names, and naturalists, for the most part, have 
adopted the arrangement of Mons. F. Cuvier, which limits the genus 
Dasypus to the single species that has teeth in the intermaxillary 
bone, and unites all the rest, excepting the Giant Armadillo, under 
the generic name Tatusia. Mr. Gray, in the ‘ List of Specimens of 
Mammalia in the British Museum,’ has adopted in addition the 
genus Xenurus of Wagler, and it will be further necessary to make 
use of Illiger’s genus Tolypeutes for the Apara or Three-banded 
Armadillo. The species v//osus and minutus must be associated, as 
Baron Cuvier has done with the Encoubert in the genus Dasypus. 
The groups recognized in the ‘Ossemens Fossiles’ being thus 
restored and the names proposed by other authors applied to them, 
I shall proceed to characterize them by their external armour, by 
which they may very easily be distinguished, and to add the cha- 
racters of the cranium, in which my observations have been assisted 
by the immortal work alluded to. 
TATUSIA. 
Ears thrown backwards and approximated ; plates of the head of 
irregular shape and smooth ; those of the scapular and pelvic shields 
much smaller than those of the bands, and surrounded with others 
smaller still; fore-feet with four toes, the claws straight, the index 
and medius nearly equal, the pollex and annularis small; maxillary 
bone terminating in a pointed process behind; teeth rather small, 
none of them being further back than the root of the malar process ; 
this process concave anteriorly, projecting outwards and backwards ; 
the infra-orbital canal entirely below it ; malar bone simply a portion 
of an inverted arch, hollowed on the outer side for nearly its whole 
length by the masseteric impression, merely abutting against the 
zygoma; palatine bone reduced in vertical extent, being encroached 
on above by a large thickened portion of the ethmoid bone which 
appears in the orbit, the sphenopalatine foramen being a narrow 
fissure between them ; pterygoid bone simply bordering the termi- 
nation of the palatine, without hamular process ; zygoma compressed 
and elevated, its glenoid surface circular ; tympanic bone reduced to 
a ring; mastoid narrowed ; lower jaw slender, its condyle but little 
elevated, transverse and flat, coronoid process elevated. 
T. SEPTEMCINCTA. 
Ears about one-third of the length of the head ; plates smooth ; 
tail as long as the body. 
T. affinis of Dr. Lund may possibly be identical. 
