170 OUTLINES OF EQUINE ANATOMY. 



Seen between tliese muscles and covered at its posterior 

 part by them is 



Splenins, a large layer of muscle attached anteriorly, in 

 common with tracbelo-mastoideus, to tbe mastoid ridge, tbe 

 crest of tbe occiput and the- wing of tbe atlas, it also has 

 heads attached to the transverse processes of the second, 

 third, fourth and fifth cervical vertebrae. Posteriorly it is 

 attached to the superior spinous processes of the three 

 anterior dorsal vertebrae, and superiorly to the cordifomi 

 portion of ligamentum nuchse along its whole length. It 

 posteriorly sends a tendon to blend with the commence- 

 ment portion of the dorsal faschia. Having removed 

 this muscle we expose another muscular layer consisting 

 mainly of complexus major, covered inferiorly against the 

 vertebrae by 



Trachelo-mastoideus, which is composed of three distinct 

 portions : 1st. Head is attached with splenius to the mas- 

 toid 2)i'ocess, and with complexus major to the oblique 

 processes of the fourth, fifth, sixth and seventh cervical 

 vertebrae, and the transverse processes of the two anterior 

 dorsal vertebrae : 2nd. Head with splenius to the trans- 

 verse processes of the two anterior and separately the 

 oblique processes of the second, third, fourth, fifth, sixth 

 and seventh ceiwical vertebrae ; 3rd. Head with splenius to 

 fourth ceiwical transverse process ; the second and third 

 heads join with the first to become attached posteriorly. 

 Between the superior tendons the oblique muscles of the 

 head are to be seen. 



Obliquus capitis superior arises from the mastoid ridge 

 and from the styloid process of the occiput, its fibres run 

 obliquely downwards and backwards, being attached inter- 

 nally to the altoido-occipital capsular ligament, and be- 

 come inserted into the anterior margin of the transverse 

 process of the atlas, at the inferior margin of this muscle, 

 slightly concealed by it, is a small muscular band, 



Obliquus capitis anticus, which runs from the styloid 

 process of the occiput to the under surface of the body of 

 the atlas at its lateral part — it is also attached to the cap- 

 sular ligament of the joint. 



Obliquus capitis inferior passes from the supero-ex- 

 ternal part of the wdng of the atlas, over the altoido- 

 dentatal joint to the capsule of which it is attached, and 

 becomes inserted into the lateral part of the superior 



