THE INTESTINES. 97 



is as follows : The fat contained in the chyme at first enters 

 only isolated epithelial cells in different regions of the villi, 

 so that in each we soon observe a large ovate shining drop. 

 The number of these fat-cells rapidly increases, and then the 

 villi acquire a very peculiar appearance, often as if beset with 

 pearls, from the irregular alternation of cells filled with fat and 

 consequently bright and shining, with those which are empty 

 and pale. In the end, all the cells become filled with these 

 drops and the epithelium appears quite dark by transmitted, 

 but whitish by reflected light, giving its aspect to the whole 

 villus. With the repletion of the entire epithelial covering of 

 the villus, absorption commences, but up to this time nothing 

 has entered the lacteals. This, however, soon takes place, 

 and the first indication we observe, is the breaking up of the 

 large drops of fat in the cells into many tolerably minute fatty 

 molecules. When this- has occurred, these drops penetrate by 

 degrees, from all sides, into the parenchyma of the villus itself, 

 fill it more and more and, at last, enter the central lacteal, whose 

 whole length they eventually occupy. In the meanwhile, fresh 

 fat has been continually passing in from the intestinal canal, 

 not in the form of large drops, however, but henceforward, in 

 small molecules or drops of the same kind as those which 

 were at first developed secondarily in the cells. On the other 

 hand, at a subsequent period, we not uncommonly meet, in 

 the interior of the villi, with large round drops, which appear 

 especially inclined to form considerable accumulations at their 

 apex. In man, I have not yet had the opportunity of tracing 

 the process of the absorption of fat, step by step, but we 

 may here so frequently observe, on the one hand, cylindrical 

 epithelial cells filled with fatty molecules, and on the other, 

 collections of larger and smaller drops of fat in the parenchyma 

 of the villi, especially at their points and in their axes, that I 

 do not at all hesitate to suppose the process to be the same as in 

 animals, without, however, wishing to imply that all the steps 

 are identical. These observations demonstrate that fatty matters 

 are absorbed as such and are not saponified ; on the other 

 hand, it cannot at present be certainly stated how it is pos- 

 sible that they penetrate the membrane of the epithelial cells, 

 the parenchyma of the villi, and the walls of the lacteals. 

 I should be most inclined to compare the whole process 

 ii. 7 



