104^ OUTLINES OF EQUINE ANATOMY. 



running from the posterior margin of the laminae of the 

 anterior vertebra, gain the anterior margin of the laminae 

 of the posterior vertebra, extending inwards as far as the 

 i7iter spinous ligame7it, which runs from the posterior margin 

 of the superior spinous process of one vertebra to the 

 anterior margin of the spine of the next bone. This is not 

 found in the cervical and coccygeal regions, and with the 

 interlaminal becomes converted into bone in the sacral. 



The sujiersjnnous ligament is a dense band of white 

 fibrous tissue extending along the upper extremities of 

 the superior spinous processes from the sixth dorsal to the 

 coccygeal vertebra. Posteriorly it becomes gradually lost. 

 In the sacral region it affords attachment to the important 

 muscles of the quarter, triceps abductor femoris, biceps 

 rotator tibialis, and ischio tibialis ; and in extending down- 

 wards on either side of the spinous processes forming that 

 flattened band which becomes attached to the oblique 

 processes termed the sacral ligament, gives attachment to 

 longissimus dorsi and to some of the muscles of the tail. 

 It is very intimately blended with the superior ilio-sacral 

 ligament and with the tendinous layer of longissimus dorsi 

 against the posterior spine of the ilium. In front of 

 this it gives attachment laterally to longissimus and latis- 

 simus dorsi and to other muscles through the medium of 

 the lumbar faschia. In the cervical region it is repre- 

 sented by 



Ligamentum nuchse. This is a remarkable body, wholly 

 composed of yellow elastic tissue, situated in the middle 

 plane of the neck, consisting of three portions, super- 

 spinous, cordiform, and membraniform. The superspinous 

 portion consists of double bands extending between the 

 superior spinous processes of the cervical and four an- 

 terior dorsal vertebrae ; they are expanded inferiorly, 

 blending with the interlaminal ligaments. Superiorly 

 they blend with the memhraniform portion which consists 

 of two thin layers of closely and somewhat irregularly in- 

 terlaced elastic fibres. These layers rest against each 

 other by their inner surfaces, inferiorly are formed by a 

 nuaiber of bands running upwards and backwards from 

 the cervical and anterior dorsal spinous processes. Thus 

 the muscles which occupy the spaces between the superior 

 spinous processes in this region lie in contact with their 

 fellows along the central plane, but those more superiorly 



