300 A MANUAL OF ANATOMY 



stance of the gland which support its lobes, and from the anterior 

 lamina fibrous bands pass to the integument, these being known 

 as the ligamenta suspensoria of Cooper. Interiorly the superficial 

 fascia is continuous with that over the anterior abdominal wall, 

 and externally it is prolonged over the floor of the axillary space 

 to become continuous with the superficial fascia of the brachial 

 region. 



The deep fascia is thin and membranous, and it closely invests 

 the pectoralis major. Superiorly it is attached to the front of 

 the clavicle above the origin of that muscle, internally it is fixed 

 to the front of the sternum, externally it is continuous with the 

 deep fascia over the deltoid, and interiorly it joins the axillary 

 fascia at the lower border of the pectoralis major. 



The axillary fascia is a firm membrane which stretches from the 

 anterior to the posterior fold of the axilla, and forms the floor of 

 that space. It is continuous in front with the deep pectoral fascia, 

 and behind it blends with the deep fascia which ensheathes the 

 latissimus dorsi. Externally it is continuous with the deep fascia 

 of the brachial region, and internally with the fascia covering the 

 serratus magnus. Its upper surface is convex, due to the fact that 

 it receives, near the pectoralis major, the clavi-pectoral fascia, 

 to be afterwards described. In this way the axillary fascia is drawn 

 upwards into the space. It is of considerable strength, and is capable 

 of affording much resistance to the pointing of an axillary abscess 

 in this direction. 



Mammary Gland. — ^This gland is situated on the surface of the 

 pectoralis major. It is somewhat hemispherical, and extends 

 vertically from the second to the sixth rib, and transversely from 

 the side of the sternum to the anterior fold of the axilla, except 

 below and externally, where it passes over that fold upon the 

 serratus magnus. A little below, and internal to, the centre of the 

 gland is the corrugated nipple, lying in the centre of a coloured 

 circle, called the areola. There is no fat beneath the nipple and 

 areola, and the skin of these parts is provided with plain 

 muscular tissue disposed circularly, which, by its contraction, 

 contributes to erection of the nipple by compressing its veins. 

 The summit of the nipple is perforated by the openings of the 

 lactiferous ducts. The skin of the areola presents a number 

 of small projections due to sebaceous glands, which are known 

 as the glands of Montgomery. The mamma is a compound race- 

 mose gland, which is composed of about twenty lobes, these in 

 turn consisting of lobules, and all being connected by a fibrous 

 stroma. The entire gland is ensheathed by the splitting of the 

 superficial pectoral fascia into two laminae, and these send processes 

 into its interior which support its component lobes. The posterior 

 layer of the sheath is loosely connected to the deep pectoral fascia 

 covering the pectoralis major, and sometimes deep processes of tht 

 gland penetrate into the substance of the muscle. The lobes an 

 pyramidal, and their apices converge toward the nipple. Each oi 



