92 Dr. Burmeister on the Species of Glyptodon 



by a description and a drawing in the second part of the work 

 of Dr. Lund (tab. 35. fig. 1). 



The seventh vertebra is moveable and tree, but maintains 

 almost the same form as one of the four which are united with 

 the axis. It is a very small bone, transversely elongated, with a 

 large, almost triquetral perforation in the centre, and three pro- 

 cesses the upper one short, and the other two strong ones at 



the sides. The lower portion, which in other Mammalia con- 

 stitutes the rather thick body of the vertebra, is a very delicate 

 plane, of scarcely any thickness in the centre, and half an inch 

 in breadth. 



The vertebral column, or spine, appears to me to be the most 

 remarkable part of the animal, it being a solid arched canal, 

 without division into separate vertebra? in conformity with the 

 rule in other mammals. This vertebral canal is bent, as the 

 form of the animal requires, and is armed in its superior part 

 with three crests, of which the middle corresponds to the spinous 

 process [neural spine, Owen], and those of the sides to the 

 transverse processes [or rather to the metapophyses, Owen] 

 of each vertebra in other ;Mammalia. But of the body [cen- 

 trum] of the vertebra, which in ]Mammalia is generally very 

 thick, nothing is seen ; and the lower part of the canal, which 

 corresponds to the bodies of the vertebra', is most fine and thin 

 in all its circumference. The canal alters in shape a little: 

 towards the fore part it is wide and low ; and towards the 

 back, little by little, narrower, but higher, and in this way the 

 three crests meet. The whole of the vertebral canal is divided 

 into three parts, of which the two anterior correspond to the 

 dorsal vertebrae, and the third to the lumbar vertebrae. 



The first part of the canal is the smallest ; beneath, in the 

 lower part, it is about 2^ inches long, and 4 inches above. Its 

 width in the middle is about 7 inches. It is composed of 

 three united vertebrae — the first small, nearly of the same 

 size as the last cervical vertebra, and the other two larger, 

 demonstrated by the holes in the sides, from which issue the 

 nerves of the myelon. The upper surface is smooth, and exhi- 

 bits a high and thick backward prolongation, which rises con- 

 siderably at the sides of the bone. Here we see two other pro- 

 longations, which correspond to the transverse processes of the 

 three vertebrae : the first is very strong, prolonged in an antero- 

 posterior direction backwards, and corresponds to the first two 

 vertebrae ; the second is very short and thin, but also broad. 

 On these processes we see the articulations of the first three 

 ribs — the first in the anterior part of the first prolongation, 

 the second in the posterior part, and the third in the exterior 

 part of the second prolongation. This first, trivertebral part is 



