7 84 GENERATION AND DEVELOPMENT. 



is, in both sexes, bounded by two folds of skin, whilst in 

 front of it there is formed a penis-like body surmounted 

 by a glans, and cleft or furrowed along its under surface. 

 The borders of the furrow diverge posteriorly, running at 

 the sides of the genito- urinary orifice internally to the 

 cutaneous folds just mentioned (see fig. 239, B, D). In the 

 female, this body becoming retracted, forms the clitoris, 

 and the margins of the furrow on its under surface are 

 converted into the nymphse, or labia minora, the labia 

 majora pudendse being constituted by the great cutaneous 

 folds. In the male foetus, the margins of the furrow at 

 the under surface of the penis unite at about the four- 

 teenth week, and form that part of the urethra which is 

 included in the penis. The large cutaneous folds form 

 the scrotum, and at a later period, namely, in the eighth 

 month of development, receive the testicles, which descend 

 into them from the abdominal cavity. Sometimes the 

 urethra is not closed, and the deformity called hypospadias 

 then results. The appearance of hermaphroditism may, 

 in these cases, be increased by the retention of the testes 

 within the abdomen. 



The Mammary Glands. 



The mammary glands, which may be considered as 

 organs superadded to the reproductive system in man and 

 other members of the class (Mammalia) which derives its 

 name from them, are, in the essential details of their struc- 

 ture, very similar to other compound glands, as the 

 pancreas and salivary glands ; that is to say, they are 

 composed of larger divisions or lobes, and these are 

 again divisible into lobules, the lobules being composed 

 of the follicular extremities of ducts, lined by glandular 

 epithelium. The lobes and lobules are bound together 

 by areolar tissue ; while, penetrating between the lobes, 

 and covering the general surface of the gland, with 

 the exception of the nipple, is a considerable quantity 



