600 THE DIGESTIVE TRACT. 



could understand the penetration of fat-granules between or into 

 the rods, but how the horny and apparently solid layer of cement- 

 substanee, serving as a base for the implantation of the rods, 

 could be penetrated by fat-granules is not intelligible. 



In 1868 I published the results of my researches during a 

 whole year (I. c., see page 401). I drew attention to the fact that 

 in specimens of uninjured villi, independently of furrows pro- 

 duced by contraction, the apices look as if split, often giving exit 

 to a mucous mass, or a portion of myxomatous tissue of the vil- 

 lus, and that in true vertical sections of the villi there are gaps 

 seen between the epithelia which are in direct connection with 



FlG. 257. VlLLUS FROM THE SMALL INTESTINE OF A GUINEA-PIG. 

 FRESH SPECIMEN. [PUBLISHED IN 1868.] 



V, vacuole in the columnar epithelium ; CV, granular (chlorophyll?) corpuscle in a vacu- 

 ole; C, granular (chlorophyll 1) corpuscles in the myxomatous tissue; S, capillary Wood-ves- 

 sel. Magnified 800 diameters. 



the central lymph-vessel, as proved, especially when both are 

 filled with fat-granules. (See Fig. 256.) Whenever colored liq- 

 uids are injected into the lymphatics of the small intestine 

 (before injecting the blood-vessels), it has long been known that 

 the colored mass escapes through the apices of the villi into the 

 intestinal canal. I have examined the small intestines of sixty- 

 eight guinea-pigs, and found, in a large majority of the villi of 



