OSTEOLOGY AND SYNDESMOLOGY. 20 
arise from-the edges of the foramen magnum, and are inserted into the 
upper border of the atlas before and behind its cblique processes. The 
lateral ligaments extend as strong cords from the transverse processes of the 
occipital bone to those of the atlas. 
Between the atlas and occiput, as already remarked, scarcely any motion 
but that of flexion and extension can occur. The turning of the head, or 
the horizontal motion, takes place between the first and second vertebre 
(the atlas and epistropheus). To this end, the articular extremity of the 
odontoid process rests on a depression on the posterior border of the ante- 
rior arch of the atlas. It is held in this position by a capsular ligament, 
but for the sake of greater security a strong, straight ligament (the trans- 
versal) extends behind it from one side of the atlas to the other. ‘The 
neck of the odontoid process is thus inclosed in a circular collar, formed by 
the arch of the atlas in front and the transverse ligament behind, in which 
_it can rotate like a pivot, being held most securely in its place (pl. 124, 
fig. 7°). The importance of this ligament is very great; in cases where it 
has become softened by disease, and ruptured, death has been instanta- 
neous; the head falling forward and the odontoid process projecting back- 
ward, has either compressed or pierced the medulla oblongata. An addi- 
tional security against dislocation is furnished by the moderator or check 
ligaments, lig. suspensorium dentis epistrophed (fig. 7 ”*), which arise ‘one 
from each side of the odontoid process,,and are inserted into a depression 
on the inner side of each occipital condyle. The two ligaments are usually 
united by a fasciculus which passes above the summit of the odontoid 
process. In addition we find a ligament, the middle occipito-axoid or appa- 
ratus ligamentosus (fig. 5°), extending from the inner surface of the basilar 
process of the occipital bone beneath the dura mater, and passing through 
the foramen occipitale, to be inserted into the superior part of the trans- 
verse ligament of the atlas, and below this into the bodies of the second, 
third, and fourth vertebre. 
In addition to the ligament extending between the head and first and 
second cervical vertebree, there are others which either extend continu- 
ously along the entire spine, or are repeated between each contiguous pair 
of vertebree. ‘These may be distinguished into two sets: those which unite 
the bodies, and those uniting the processes. The first comprise the anie- 
rior and posterior common vertebral ligaments and the intervertebral fibro- 
cartilages or ligaments; the second set include the capsules and synovial 
membranes of the oblique. processes, the infra-spinous or yellow ligaments, 
the inter-spinous, the supra-spinous, and the inter-transverse. The bodies 
of the vertebra are united by an anterior, a posterior, and an intervertebral 
ligament. 
The antervor vertebral ligament (pl. 124, fig. 4”) is a strong band of fibres 
extending from the atlas to the sacrum along the anterior face of the spine, 
and adhering strongly to the bones, particularly to their edges and to the 
intervertebral substances... Its object is to attach the vertebre together, to 
strengthen the intervertebral ligaments, and to oppose excessive extension 
of the column. 
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