Costo-vertebralis Lateralis (Longus colli). Originates thin and sharp on the body of the fifth thoracic vertebra, increases in thickness slowly but decidedly cephalad, then again becomes thinner and inserts itself on the inner side of the ribs of the most anterior two cervical vertebræ.
Collo-capitis (Rectus capitis anterior). Arises, as a rule, from the cervical centra, at times from the second thoracic vertebra (Gavialis). It extends forward and is inserted on the basi-occipital and the hinder border of the pterygoid. For a greater part of their length the two muscles lie close together, but forward they separate somewhat from each other.
Dorsal Neck Muscles
Occipito-cervicalis Medialis (Complexus cervicis, Biventer cervicis, Zweibäuchiger Strecker or Zweibäuchiger Nackenmuskel, Splenius capitis). It springs, by separate points, from the dorsal processes of the four anterior body vertebræ and the six posterior neck vertebræ; it is convex on its dorsal, weakly concave on its ventral surface; it leads cephalad as a short, strong tendon by which it is attached to the angle between the upper hinder border of the skull, i.e. to the superior and lateral occipital region.
Squamoso-cervicalis Medialis (Kopfbäuchmuskel [Splenius] or durchflochtener Muskel [Complexus], Trachelo-mastoideus, Complexus). This muscle lies laterad and ventrad to the preceding and is at times partly covered by it in its posterior half. It arises from separate heads from the spinal processes of the two anterior and six posterior cervical vertebræ; beginning caudad, thin and sharp, it gradually becomes thicker as it passes cephalad until it becomes partially tendinous and inserts itself on the hinder border of the squamosal, laterad to the occipito-cervicalis medialis muscle.
Epistropheo-vertebralis (Splenius colli). This muscle springs from the spinous processes of the most anterior three body vertebræ and the last cervical vertebra; it receives fibers from the articular processes and intermediate parts of the six posterior cervical vertebræ and is inserted on the second cervical vertebra.
Collo-squamosus (Splenius capitis, Nackenwarzenmuskel, Trachelo-mastoideus). Springs from the upper transverse processes of the last three neck vertebræ, and, becoming tendinous, is inserted on the hinder border of the squamosal.
Collo-occipitis. Arises from the transverse processes of the posterior five cervical vertebræ, extends directly forwards on the ribs of the vertebræ, and is inserted under the articular surface of the lateral occipital.
Occipito-epistropheus (short, straight, hinder head-muscle, or extensor). This muscle springs from the lateral surface of the body of the second neck vertebra and inserts itself on the basi-exoccipital, under the preceding muscle.
Cervicalis Adscendens. Arises in great part from the angles under the most anterior ribs; a smaller part appears farther above where it is covered by the rhomboideus muscle. It is inserted on the upper side of the five posterior cervical ribs and on the distal ends of the long second cervical rib.