ABSORPTION OF FAT. 295 



the passage of the fats into the intestinal villi. Wagner has assumed 

 that some portions of the intestinal canal are intended solely for 

 the absorption of the fats, and others only for taking up the 

 aqueous fluid. We should, however, rather be disposed to assume 

 with Lenz* that certain cells in each intestinal villus are solely des- 

 tined for the absorption of fat, a mode of explanation which would 

 be especially convincing to the chemist, who is accustomed to 

 separate fatty from aqueous fluids by means of a filter saturated 

 in one case with water, and in the other with oil. If we con- 

 stantly observed (as we might often do) that the apex of each intes- 

 tinal villus exhibits one vesicle more conspicuous than others for 

 its size, and filled with a clear, strongly refractive fluid, together 

 with another equally prominent vesicle, filled with granular matter, 

 we should the more readily be led to the adoption of this hypothesis, 

 since it affords an explanation of the view advanced by Bous- 

 singault, and confirmed by Bidder and Schmidt, that the absorption 

 of fat from the intestine is confined within definite limits. Lenz 

 adopted a very ingenious method for the further support of this 

 hypothesis, which, however, did not prove so satisfactory as might 

 have been desired. He injected butter, that had been coloured 

 with alcanna pigment, into the stomachs of cats, and killed the 

 animals some hours afterwards. Most of the cells were found to 

 be filled with yellowish fat, but this appearance could not afford 

 any decisive explanation of the subject under consideration. How- 

 ever ingeniously this experiment \vas conceived, its frequent repe- 

 tition was scarcely calculated to yield perfectly reliable results, for 

 the fat would certainly become mixed in some places with the 

 aqueous fluid, and as it would have to penetrate through several 

 cells before it reached the smaller lacteals, it would enter those 

 vessels mixed with the watery fluid; and this admixture would 

 likewise go on in the villi of the cells surrounding the origins of the 

 lacteals. If the cells filled with fat, and situated on the periphery 

 of the villi and at their outer extremities, did not differ so strongly 

 from the others, it would be illogical to attempt to explain the 

 occurrence of a process in the interior which has been regarded as 

 improbable at the surface, the relations existing in both being very 

 nearly identical. Here, however, these relations are somewhat dif- 

 ferent, for we find some cells containing fat, and others filled with 

 an albuminous fluid, appearing to be closely compressed together 

 This pressure may easily exert a modifying action on the perme- 

 ability of the delicate cell-membranes, in the same manner as we 

 * Op. cit. p. 8689. 



