MAMMARY GLAKDS. 73 



peculiar interest, aside from the great importance of their 

 secretion. 



It will be found convenient to consider these organs in 

 three stages of development ; viz., in their rudimentary con- 

 dition, as they exist in the male and in the female before 

 puberty ; in the partially-developed state, as they are found 

 in the unimpregnated female after puberty and during the 

 intervals of lactation ; and finally, in the fully-developed 

 condition, when milk is secreted. 



Physiological Anatomy of the Mammary Glands. 



The form, size, and situation of the mammae in the adult 

 female are too well known to demand more than a passing 

 mention. These organs are almost invariably double, and 

 are situated on the anterior portion of the thorax over the 

 great pectoral muscles. In women who have never borne 

 children, they are generally firm, nearly hemispherical, with 

 the nipple at the most prominent point. In women who 

 have borne children, the glands, during the intervals of 

 lactation, are usually larger, are held more loosely to the 

 subjacent parts, and are apt to become flabby and pendu- 

 lous. The areola of the nipple is also darker. 



Certain rare examples are on record of anomalies in the 

 number and location of the mammary glands. In some in- 

 stances three, four, and five distinct glands have existed 

 instead of two ; * and some examples are related of extra- 

 ordinary development of the mammary glands in the male, 

 to such an extent as to afford sufficient nourishment for an 

 infant. 8 A remarkable case of malposition of a mammary 

 gland is reported by Dr. Eobert, of Marseilles, in Magendie's 



1 Reference to a number of these cases is made by Dr. Solly, in the Cyclo- 

 pcedia of Anatomy and Physiology, London, 1839-1847, vol. iii., p. 251. 



8 Quite a number of cases of this kind are on record, many of them well 

 authenticated. Dr. Dunglison gives a full account of several instances of lac- 

 tation in the male, attested by competent medical observers. (DUNGLISON, 

 Human Physiology, Philadelphia, 1856, vol. ii., p. 520.) 



