run in Man and certain of the Mammafia. 167 



table, forced itself upon me ; and the existence of milky chyle, 

 within closed cells, led me to anticipate an explanation of some 

 of the phenomena of digestion. 



A dog was fed with oatmeal, milk, and butter. Three hours 

 afterwards he was killed, and a cord thrown round the root of 

 the mesentery. The lacteals became more turgid, and the gut, 

 when opened, was found to be full of milky chyme, with an 

 admixture of thin brownish fluid of a bilious appearance. 

 The milky matter was situated principally towards the mucous 

 membrane ; the brown fluid occupied the cavity of the gut. 



The white matter was found to consist of a transparent fluid, 

 with a few oil globules, and numerous epithelia. 



Some of the epithelia I recognised as those which cover the 

 villi. They were pointed at their attached extremities, flat at 

 the other. (Fig. 1. PI. I.) Many of them were single, others were 

 united in bundles, adhering principally by their flat or free 

 extremities, as if a fine membrane passed over and connected 

 the edges of their extreme surfaces. (Fig. 2, PI. I.) Occasion- 

 ally these epithelia presented a distinct nucleus ; but generally, 

 and whether single or in bundles, they exhibited in their in- 

 terior a group or mass of oil-like globules, which, when view^ed 

 as opaque objects, had a peculiar semi- opaque or opalescent ap- 

 pearance*. (Fig. 3, PI. I.) Others of the epithelia, contained in 

 the chyme, were prismatic, single, or in columns. (Fig. 4, PI. I,) 

 They were the lining epithelia of the follicles of Lieberkiihn, 

 and presented the usual nuclei. 



The mucous membrane displayed the villi turgid as if in 

 a state of erection, and, as I had anticipated, naked or des- 

 titute of epithelia. except at their bases where a few still 

 adhered. Each villus was covered by a very fine smooth 

 membrane, which from its free bulbous extremity, passed on 

 to its sides, and became continuous with what I have else- 

 where denominated the primary membrane (Trans. Roy. Soc. 

 Ed. 1842) of the follicles of Lieberkuhn. (Fig. 8, PI. I.) "^These 

 villi when removed from the mucous membrane, and examined 

 with J inch magnifier, were semi-transparent, except at their 

 free or bulbous extremities, which appeared both by direct or 



* Is this appearimcc due to a partiRl absorption of chyle by these pro- 

 tective epithelia \ 



