138 



THE STRUCTURE OF THE HORSE 



wards, and forming together the ridge of the middle 

 of the back. Those of the third, fourth and fifth 

 vertebrae, which are situated between the shoulder- 

 blades, are the longest, and correspond externally to 

 the £ withers,' the highest point of a horse's back, across 

 which the measuring-rod is placed when taking his 

 height. 



The upper contour of the neck of the living horse is 

 altogether different from that of the skeleton, the great 

 depression seen in the latter in front of the high spines 

 of the thoracic vertebrae being filled up in the middle 

 line by a remarkable structure called the c cervical liga- 

 ment,' and on each side of this by large masses of 

 muscles which raise and turn the head, and above all by 

 the median 4 crest,' a soft but firm, fibrous, and fatty 

 ridge immediately beneath the skin from which the 

 mane grows. 



The cervical ligament (ligamentum cervicis, liga- 

 mentum nuchce or 4 pack wax ' ), which in man is quite 

 rudimentary, as his head, balanced on the top of the 

 vertebral column, requires no special support, is im- 

 mensely developed in the horse. It consists mainly of 

 a strong elastic cord, which is attached in front to the 

 upper part of the back of the skull (fig. 22, o), and 

 posteriorly to the elongated spines of the dorsal verte- 

 brae (s). Between this, the funicular part of the cer- 

 vical ligament, as it is called, and the bones of the 



