412 



2285. The right astragalus. 



Its anterior articulation is expanded, and seems to be supported on a neck. The tibial 

 trochlea is unusually oblique in reference to the grasping power of the hind foot. 



2286. The right calcaneum, with the scaphoid, cuboid, and internal accessory 

 ossicle. 



The following are parts of the same skeleton of the Grey Squirrel (Sciurus cinereus) : 



Hunterian. 



2287. The sacrum. 



2288. The right os innominatum. 



This shows the ordinary ischial tuberosity between the one which articulates with the first 

 caudal vertebra and that which is next the symphysis. 



2289. The caudal vertebrae. 



These are 26 in number. The posterior ones are remarkable for their length and tenuity, 

 having to sustain only the light bushy tail. This serves as a balancer in leaping, and as a 

 blanket when the animal sleeps. 



Order BRUTA. (EDENTATA, Cuvier.) 

 Genus Dasypus. 



2290. The skeleton of the Weasel-headed Armadillo (Dasypus sextindus). 



The vertebral formula is : 7 cervical, 1 1 dorsal, 3 lumbar, 9 sacral, and 1 6 caudal. The 

 second and third cervicals have coalesced together, and they develope a strong confluent 

 lie u nil spine. The last four cervicals are without those spines, and are equally devoid of 

 zygapophyses. The diapophysis of the last cervical contributes to the articular cavity for 

 the tubercle of the first dorsal rib, which is enormously expanded ; and the anchylosed 

 pleurapophysis of the seventh cervical projects backwards beneath the head of the first dorsal 

 rib. The neurapophyses of the middle dorsal vertebrae are directly perforated for the spinal 

 nerves. Anapophyses are developed from behind the diapophyses of the first three dorsals ; 

 they decrease in size in the succeeding dorsals, but again increase in the posterior dorsals and 

 in the lumbar vertebrae, where they present an articular surface to the metapophysis of the 

 succeeding vertebrae. The metapophyses commence as ridges on the upper surface of the 

 diapophyses of the second and third dorsals ; they form prominent tubercles on the seventh 



