136 THE ANATOMY OF THE HORSE. 



The Costo-vertebral or Stellate Ligament is placed beneath the joint. 

 Its fibres radiate from the rib just below its articular head, and become 

 attached to the body of the vertebra in front, to the body of the 

 vertebra behind, and to the intermediate disc. 



The Interarticular Ligament is fixed to the groove dividing the articular 

 head of the rib into two facets. It passes inwards across the floor of 

 the spinal canal, being united to the upper edge of the intervertebral 

 disc ; and on the middle line it becomes continuous with the corre- 

 sponding ligament of the opposite rib. It is not present in the 1st rib. 

 It should be displayed by disarticulating the costo-transverse joints of 

 the first vertebra in the segment, and then removing the arch. On 



Fig. 10. 



t\vo costo-vektebral, and two intervertebral joints, viewed from above. 

 The Lamin.-e ok the Vertebr.k have been removed. 



1. Posterior costo-transverse ligament; 2. Anterior (interosseous) costo-transverse ligament. 

 3, 3. Superior common ligament. 



removing the superior common ligament it will be found in the interval 

 between the two vertebral bodies. 



Synovial Sacs. — There is one sac on each side of the interarticular 

 ligament. There is only one sac for the first costo-central joint. 



Costo-transverse Joint. This is maintained by two ligaments — an 

 anterior and a posterior costo-transverse ligament, and it possesses a 

 synovial sac. 



The Posterior Costo transverse Ligament is composed of a band of 

 fibres stretching across the joint behind, and fixed by its extremities 

 to the rib and transverse process. 



The Anterior {Lnterosscous) Costo-transverse Ligament stretches between 

 the anteroinferior aspect of the transverse process and the neck of 

 the rib. It is partly concealed by the transverse process, and is best 

 seen when viewed from above and in front. 



