MAMMAE. 319 



CHAPTER XXII. 



OF THE MAMMAE OR BREASTS. 



THE glands are organs destined for secreting from the blood 

 certain liquids, useful or indipensable for various purposes of the 

 animal economy. They consist of a congeries of vessels, and can- 

 not, therefore, be subjected to a chemical analysis with any ad- 

 vantage. But it may be worth while, in this and some subse- 

 quent chapters, to state shortly the structure of some of the most 

 important glands, so far as it has hitherto been ascertained by 

 anatomical examination. 



The mammce or breasts are two round eminences placed one at 

 each side, on the front of the thorax, resting on the pectoral 

 muscles. They are fully developed in females, to whom they 

 belong, at the age of puberty. The mamma is a conglomerate 

 gland, consisting of several small lobes, each being an aggregate 

 of a number of lobules. Each lobule is about the size of a mil- 

 let-seed, oblong in shape and hollow. It consists of a mucous 

 lining, and an envelope of cellular tissue, in which the secreting 

 vessels ramify. From the lobules thus formed arise the minute 

 radicles of the lactiferous tubes, which receive the milk as it is 

 secreted. The tubes converge towards the nipple, so as to be- 

 come collected into a fasciculus beneath it, in which situation 

 they are supported by some firm cellular tissue. The number 

 of fasciculi varies from twelve to fifteen, and each belongs to a 

 particular lobe of the gland. Four, six, or eight, minute ducts 

 unite to form one lactiferous tube, which inclines to the areola, 

 where it dilates somewhat ; but at the base of the nipple it nar- 

 rows again, and runs in a straight course from its base to its sum- 

 mit, where it terminates. The tubes are lined throughout by a 

 mucous membrane, which permeates the whole of their extent, 

 and even covers the lobule. " This inner lining appears to be en- 

 closed in another tunic formed of cellular tissue. 



From this description it appears that the mammse, if we ab- 

 stract the numerous vessels which cover every lobule, and which 

 are too minute and intricate to admit of a chemical examination, 

 are composed of cellular tissue lined with mucous membrane 

 and therefore similar to what has already come under our review. 



