CHAP, in.] SKELETON OF THE HEAD AND TRUNK. 55 



Another ligament, the ventral occipito-atlantal ligament, passes 

 from the front ventral border of the atlas forwards to the adjacent 

 part of the skull, and similarly the ventral atlanto-axial ligament 

 connects the ventral arch of the atlas with the centrum of the 

 axis. Certain other ligaments connect together the neural arch of 

 the atlas with that of the axis and with the skull. The first of 

 these is the dorsal atlanto-axial ligament, connecting the neural 

 arches of the axis and atlas. Another is the dorsal occipito-atlantal 

 ligament (Fig. 27, T ), which connects the neural arch of the atlas 

 with the adjacent margin of the posterior aperture of the cranium. 

 A third ligament, the transverse atlanto-occipital ( 5 ), passes outwards 

 upwards and forwards on each side from the neural arch of the atlas 

 to the inner side of the adjacent occipital condyle. Yet another liga- 

 ment may he called interspinous. It connects the neural spine of the 

 axis with the middle of the dorsum of the neural arch of the atlas. 



31. As to the ribs, a ligament, named " stellate" passes, in a 



Fig. 27. LIGAMENTS OF ATLAS AND Axis. 



1. Dorsal occipito-atlantal ligament. 



2. Dorsal atlanto-axial ligament. 



3. Interspinous ligament. 



4. Rectus lateralis muscle. 



5. Transverse atlanto-occipital ligament, 

 so. Supra-occipital. 





radiating manner, from the ventral surface of the head of each rib 

 on to the intervertebral substance opposite to it, and on to the bodies 

 of the two adjacent vertebrae. 



Another ligament, named inter-articular, passes transversely from 

 that ridge on the head of the rib which divides its two articular 

 surfaces, to the intervertebral substance. This ligament of course 

 does not exist in the articulations of the first, eleventh, twelfth, and 

 thirteenth ribs, which have each but one articular surface. 



The ribs, except the first and the last three, are also connected 

 with the transverse processes, each by certain other ligaments ; but 

 none of these attachments prevent each rib from performing a slight 

 movement backwards and forwards upon its vertebral attachment, m 

 well as a certain movement of rotation. 



The pieces of the sternum are connected by cartilage, and bound 



