INTERNAL MAMMARY ARTERY. 287 



The SUPERFICIALIS CERVICIS ARTERY (cervicalis anterior) is a small 

 vessel, which ascends upon the anterior tubercles of the transverse 

 processes of the cervical vertebrae, lying in the groove between 

 the scalenus anticus and rectus anticus major. It is distributed to 

 the deep muscles and glands of the neck, and sends branches 

 through the intervertebral foramina to supply the spinal cord and 

 its membranes. 



The PROFUNDA CERVICIS (cervicalis posterior) passes backwards 

 between the transverse processes of the seventh cervical and first 

 dorsal vertebra, and then ascends the back part of the neck, 

 between the complexus and semi-spinalis colli muscles. It inoscu- 

 lates above with the princeps cervicis of the occipital artery, and 

 below, by a descending branch, with the posterior scapular. 



The SUPERIOR INTERCOSTAL ARTERY descends behind the pleura 

 upon the necks of the first two ribs, and inosculates with the first 

 aortic intercostal. It gives off two branches which supply the two 

 first intercostal spaces. 



The INTERNAL MAMMARY ARTERY descends by the side of the 

 sternum, resting upon the costal cartilages, to the diaphragm : it 

 then pierces the anterior fibres of the diaphragm, and enters the 

 sheath of the rectus, where it inosculates with the epigastric artery, 

 a branch of the external iliac. In the upper part of its course it is 

 crossed by the phrenic nerve, and lower down lies between the 

 triangularis sterni and the internal intercostal muscles. 



The Branches of the internal mammary are, 



Anterior intercostal, 



Mammary, 



Comes nervi phrenici, 



Mediastinal, 



Pericardiac, 



Musculo-phrenic. 



The Anterior intercostals supply the intercostal muscles of the 

 front of the chest, and inosculate with the aortic intercostal arteries. 

 Each of the three first anterior intercostals gives off a large branch 

 to the mammary gland, which anastomoses freely with the thoracic 

 branches of the axillary artery ; the corresponding branches from 

 the remaining intercostals . supply the integument and pectoralis 

 major muscle. There are usually two anterior intercostal arteries 

 in each space. 



The Comes nervi phrenici is a long and slender branch which 

 accompanies the phrenic nerve. 



The mediastinal and pericardiac branches are small vessels dis- 

 tributed to the anterior mediastinum, the thymus gland, and peri- 

 cardium. 



The Musculo-phrenic artery winds along the attachment of the 

 diaphragm to the ribs, supplying that muscle and sending branches 

 to the inferior intercostal spaces. " The mammary arteries," says 





