210 



HISTOLOGY. 



After the spherules had broken down and probably been transferred to the 

 blood vessels, the tunica propria entered into its usual relation with the 

 shortened epithelium (D). The basal protoplasm was then restored. 

 Thus proteid absorption was accomplished as a secretory process of the 

 epithelium, the product being eliminated from its basal portion. The 

 spherules accumulate at and near the tips of the villi in spaces which many 

 authorities, including Professor Stohr, describe as due to the artificial 

 retraction of the tunica propria (Fig. 231, a). The spherules have been 

 considered a coagulum of the fluid squeezed from the reticular tissue. 

 In part they may be the boundaries of the basal ends of epithelial cells on 

 the distal wall of the villus. Often a delicate connective tissue artificially 



FIG. 237. DIAGRAM OF A 

 MESENTERY AS SEEN IN 

 CROSS SECTION OF THE 

 ABDOMEN. (After Minot.) 



a., Aorta; c. p., cavity of the 

 peritonaeum ; int., intes- 

 tine; mes., mesentery; p. 

 m. and v. m., parietal and 

 visceral layers of meso- 

 thelium. 



FIG. 238. SURFACE VIEW OF THE GREATER OMENTUM FROM 

 A RABBIT. X 240. 



Thick and thin connective tissue bundles form meshes. The wavy 

 striation of the bundles is obscured since the preparation is 

 mounted in balsam. At x the epithelial cells of the opposite 

 surface are visible. 



shrinks from an epithelium, as seen in Fig. 22, p. 23. On the other hand, 

 these considerations are familiar to those who interpret the spherules as 

 the result of proteid absorption. It is well known that a certain amount of 

 proteid is absorbed in the large intestine, and it has recently been found, 

 by Dr. J. L. Bremer, that beneath its epithelium, reticular appearances 

 similar to those in the small intestine occur after proteid digestion. 



The muscularis mucosae of the small intestine consists of an inner 

 circular and an outer longitudinal layer of smooth muscle. The submucosa 

 is of loose -fibrous connective tissue with few elastic fibers. The mus- 

 cularis includes an inner circular layer of smooth muscle fibers, and a much 

 thinner outer longitudinal layer. Between them is a narrow but important 

 band of connective tissue. Numerous elastic fibers are found not only 



