PHYSIOLOGICAL FATTY METAMORPHOSIS. 361 



ordinary absorption of fat from the intestiial canal. 

 When we drink milk, we expect in accordance with old 

 experience that it will gradually pass from the intestines 

 into the lacteals, and thence be conveyed into the blood ; 

 we know that the passage of digested matters from the' 

 intestines into the lacteals takes place through the epithe- 

 lium and the villi, and that some hours after a meal the 

 epithelium and the villi are full of fat. Now, with respect 

 to such a fat- containing villus or epithelial cell, we take 

 for granted that in the natural course of events it will at 

 last yield up its fat, and after some time again become 

 perfectly free from it. This is fatty infiltration of a 

 purely transitory character. 



Finally, we have a third series of processes, namely 

 those which lead to necrobiosis and which have of late 

 frequently been regarded as peculiarly pathological ones. 

 But, as it has been shown to be the case in all other con- 

 ditions that pathological processes are not specific ones, 

 but, on the contrary, that others analogous to them exist 

 m normal life, so also the conviction has been acquired 

 that this necrobiotic development of fat is an entirely 

 regular and typical process in certain parts of the body, 

 nay that it is even met with in very obvious forms in 

 physiological life. The most important types of this pro- 

 cess we find on the one hand in the secretion of milk 

 the sebaceous matter of the skin, the cerumen of the ears,' 

 etc., and on the other in the formation of the corpus lu- 

 teum in the ovaries. In all these parts a development 

 of fat takes place precisely in the same manner that we 

 meet with it in the nocrobiotic fatty metamorphosis 

 occurring from morbid causes, and in what we calf seba- 

 ceous matter, milk or colostrum we have formations ana 

 logous to the pathological masses of fat which constitute 

 fatty softening. If in any person milk is manufactured 

 m the brain instead of in the mammary gland, this con- 



