STRUCTURE OF THE INTESTINE 



153 



The mucous membrane of the large intestine is beset with simple 

 tubular glands somewhat resembling the crypts of Lieberkiihn of the 

 small intestine, and lined by columnar epithelium similar to that 

 of the inner surface of the gut, but containing many more mucus- 

 secreting or goblet cells (fig. 186). The extremity of each gland is 

 usually slightly dilated. The interglandular tissue is like that of the 



FlG. 186. A GLAND OF THE 

 LARGE INTESTINE OF THE DOG. 



(From Heidenhain and Klose.) 



b, in longitudinal, c, in transverse 

 section. 



stomach, as is also the arrangement of the blood-vessels and lymphatics 

 in it. The nerves of the large intestine also resemble those of the 

 small intestine and stomach in their arrangement. 



At the lower end of the rectum the circular muscular fibres of the 

 gut become thickened a little above the anus so as to form the internal 

 sphincter muscle. In this region also there are a number of compound 

 racemose mucous glands opening on to the surface of the mucous 

 membrane. 



