96 ANATOMY or THE DOMESTIC POWL 



tendons from the under side of the ends of the first three or four 

 caudal vertebrae. 



Insertion. — To the side of the posterior margin of the expanded 

 portion of the pygostyle. 



Shape. — Subcompressed mass. 



Relations. — With the transverse processes of the caudal vertebra, 

 inferiorly. 



Action. — Controls the lateral movements of the tail and its 

 feathers, and the obUque downward movement. 



Infracoccygis (Fig. 25, No. E, i). Location. — The extreme in- 

 ferior portion of the caudal vertebrae. 



Origin. — ^From the inferior surface of the diapophysiS of the last 

 vertebra which anchyloses with the pelvic sacrum, and from all the 

 free caudal vertebrae. 



Insertion. — Into the lower side of the pygostyle. 



Shape. — ^Flat, somewhat triangular. 



Relations. — Superiorly, with the vertebrae, laterally, with the 

 lateraKs coccygis, and mesially, with its fellow of the opposite side. 



Action. — ^Depresses the tail. 



THE COSTAL REGION 



Latissimus dorsi Trapezius 



Rhomboideus Serratus magnus anticus 



Serratus parvus anticus Teres et infraspinatus 



Intercostales Levatores costarum 



Appendico-costales 



Latissimus Dorsi (Fig. 24, No. 7). Location. — Supero-lateral por- 

 tion of the dorsal region. 



Origin. — From two portions, the anterior sUp from the outer edge 

 of the superior margins of the neural spines of the second and the 

 third dorsal vertebrae, and the second portion from a similar point 

 on all the succeeding dorsal vertebrae. The second portion is fascia- 

 like in its attachments. 



Insertion. — The fibers converge toward the humerus and enter 

 between the deltoid the scapular head of the triceps and the re- 

 maining heads of this muscle and is inserted to the anconal part 

 of the humerus, just within in the radial crest. 



