1430 



The prepuce is formed by the growth of a solid plate of ectoderm into the superficial part of 

 the genital tubercle; on coronal section this plate presents the shape of a horseshoe. By the 

 breaking-down of its more centrally situated cells this plate is split into two lamellae and a 

 cutaneous fold, the prepuce, 1 is liberated and forms a hood over the glans. " Adherent prepuce 

 is not an adhesion really, but a hindered central desquamation" (Berry Hart, op. cit.). 



The homologies of the different parts of the sexual organs may be stated in tabular form as 

 follows: 



THE MAMMARY GLAND (MAMMA) (Figs. 1191, 1193). 



The breasts, mammary glands or mammae, secrete the milk, and are accessory 

 glands to the organs of reproduction. They develop fully in the female, but 

 usually remain rudimentary in the male. There are two of these glands, and 

 they are situated in the superficial fascia of the anterior portion of the thorax. 



Description of a Well-developed Breast. Each gland appears as a hemispher- 

 ical body projecting from the front of the thorax beneath the skin and lying over 

 a portion of the Pectoralis major muscle and a smaller portion of the Serratus 

 magnus muscle. The hemispherical projection extends usually from the margin 

 of the sternum to the axilla and from the level of the second rib to the level of the 

 sixth rib, or from the third rib to the seventh rib, but this does not represent 

 the real size of the gland. The gland is much larger than this, being rendered 

 so by tails or prolongations of breast tissue, which will be described later (p. 1432). 



The nipple (papilla mammae) (Figs. 1190 and 1193) projects from a little 

 below and to the median side of the summit of the hemisphere at or above the 

 level of the fifth rib, and is covered with thin skin. The right nipple may not 

 exactly correspond in situation and direction to the left nipple. The nipple 

 varies considerably in height and shape. In the virgin it is usually cylindrical 

 and is directed forward and slightly upward and outward. The apex of the 



