572 THE LARGE INTESTINE. 



gives only a partial covering, and is studded all along the 

 large intestine with little reflections containing fat, called 

 appendices epiploicce. In the ascending and descending 

 colons, the peritoneal reflections are such as to receive the 

 names of right and left mesocolon. The arch of the colon is 

 almost entirely surrounded, has great facility of motion, 

 and is kept in its place "by the reflection termed transverse 

 mesocolon. This reflection goes back to the spine and 

 divides the abdominal cavity into two parts, thus separating 

 the stomach, liver, and spleen above, from the intestines 

 below. The rectum is kept in position by the reflection 

 termed meso-rectum. 



The muscular coat differs from that of the small intes- 

 tine, in having its longitudinal fibres collected into three 

 bands, which are equi-distant and about an inch in breadth; 

 one of these bands is anterior, another internal, and the 

 third external. These are white, strong, and elastic, and 

 being shorter than the other coats, produce constrictions in 

 its course, giving to this intestine a cellular , sacculated, or 

 pouch-like appearance. These cells or pouches disappear 

 when the bands are divided. These delay the too rapid 

 passage of the faeces. 



The mucous coat differs from that of the small intestine 

 in being almost if not entirely destitute both of villi and 

 valvulae conniventes. The rugge that are seen on its sur- 

 face do not belong to the mucous coat alone, but are formed 

 by the other coats. Each of the different divisions of this 

 intestine has peculiarities requiring separate notice. 



The coecum, (Fig. 184 3 A) securely fastened in the right 

 iliac fossa by the peritoneum, is from an inch to two inches 

 in length, rounded below and convex externally. 



From its posterior inferior portion on the left side, it 

 gives off a tortuous process, called appendix vermiformis, 

 about the size of a goose quill, and varying in length from 

 three to six inches. Its position also varies. It has a 

 peritoneal covering which allows it to float loosely, and 

 it is sometimes the cause of much mischief by surround- 

 ing the ilium and producing strangulation. It is tubular. 



