648 



Distribution of the milk-ducts in the Mamma of the Human female, during lactation; the ducts 



injected with wax. 



the simplicity and uniformity of their divisions. It is very rarely, however, that they inos- 

 culate. The mammary ducts are composed of a fibrous coat lined by a mucous membrane ; 

 the latter is highly vascular, and forms a secretion of its own, which sometimes collects in 

 considerable quantity when the milk ceases to be produced. 



b. The gland itself is composed of the union of a number of glandules, which are con- 

 nected by means of the fibrous or fascial tissue of the gland ; it is between these, that the 

 mammary tubes may be observed to ramify; and from them their branches spring. When 

 the glandules arc rilled with injection, and for a long time macerated in water and un- 

 ravelled, they are found to be disposed in lobuli; and when a branch of mammary tube is 

 separated, with the glandules attached, the part appears like a bunch of fruit hanging by its 

 stalk. When the lactiferous tube proceeding from a glandule is minutely injected, the latter 

 will be found to be composed of numerous follicles, in which the ultimate ramifications of 

 the former terminate, or rather originate. Their size, in full lactation, is that of a holt- 



Fig. 203. 



Fig. 254. 



Termination of portion of milk- 

 duct in a cluster of follicles ; from 

 a mercurial injection ; enlarged 

 four limes. 



Uhirnate follicles of Mammary 

 gland, with their secreting cells, 

 a, a;b, b, the nuclei. 



