137 



one of tlie perfections of form, adapting tliat animul to ils siihUTra- 

 neous mode oi' life. In the ArmailUlo, however, the burroMs serve 

 only as temporary retreats ; for it is endowed wilh po\vers of rapid 

 progrcssion on the surface, and its organ of vision, though small, is 

 accordingly perfect. Thus the pelvis is destined to afford attach- 

 ment to numerous and povverful museles, and the hind-legs are 

 evidently of considerable use in clearing out the burrovv, as may 

 be inferred from the action of the ArmadUlo \vhen he hides him- 

 self in the stravv, \vhich he throvvs behind him vvith great force : 

 vvhereas in the Mole, the vvhole povver of digging is concentrated in 

 the anterior extremities, the peciiliar mechanism of vvhich is admi- 

 rably adapted to that act. 



" The caudul vertebrce, likę the cervical, present in Dasypus a pe- 

 culiarity which is also found in the Cetacea, viz. that of having infe- 

 rior spines, or V-shaped bones. These are present beneath all but the 

 two lašt vertebrce ; they are of a triangular form, but are articulated, 

 not by their bases, as in the ll'hale, but by their apkės ; or rather the 

 part which corresponds to the apex is flattened, and produced into 

 two lateral processes. 



" With respect to the bones of the extremities, it may be remarked 

 that the scapula is very concave tovvards the ribs, more so than in the 

 nine-banded species ; and that besides the two spines, there is also a 

 third ridge near the superior costa. Below the articular surface on 

 the inferior costa there is also a little tubercie, vvhich does not exist 

 in Das. Peba. The supra-spinal notch is large, and the acromion 

 long and narrow, but not anchylosed, as in the Slotli and Megathe- 

 rium, to the coracoid. The length of the scapula, from the base to 

 the articular surface, is 2 inches J line ; of the base, 2 inches ; of the 

 acromion, 1 1 lines. The clavicles in Das. 6-cinctus are siightly 

 curved, and are shorter and stronger than in Das. Peba : their length 

 is Ii inch. There is thus a correspondence betvveen the clavicle 

 and the ręst of the anterior estremity, the claws being stronger, 

 and the whole of the bones shorter and thicker than in Das. Peba. 

 The humerus measures in length 2 inches 3-lOths: at the upper 

 extremity are two large tuberosities and a deep middle groove ; 

 about the middle of the bone is a strong deltoid process : the bone 

 is considerably tvvisted, and the inner condyle perforated as in most 

 Edentata. The supinator ridge is strongly marked j the anconeal 

 fossa large and shallovv. 



" The ulna measures in length 2 inches 3-lOths ; ic is a very strong 

 bone, compressed, and arched backvvards : the extremity of the ole- 

 cranon is bent backvvards in the form of a hook : the lovver extre- 

 mity has an equal share with the radius in the articulation with the 

 carpal bonrs. The radius is in length 1 inch 4 lines. The large pal- 

 mar sesamoid bone,formed at the expense of the tendons of thc^eror 

 profundus digitorum, is shaped likę the head of a Tspade, with the 

 concavity tovvards the carpus, and ihe sharp margin anterior : in length 

 and breadth it measures half an inch. It is articulated by a distinct 

 capside and synovial membrane vvith the ossa pisiforme and cuneiforviė 

 on one side, and to the naviculurc on the otlicr. TheJĮexor profundus 



