1 8 MUSCLES OF THE ABDOMEN 



curvature of the duodenum is the pancreas ; its at- 

 tachments must not be disturbed. 



b. The Small Intestine is several feet in length, 

 and forms a very much convoluted tube which is at- 

 tached to the dorsal wall of the body by a membrane, 

 the mesentery. Starting from the duodenum, follow 

 the small intestine to its ending in the large intestine. 



c. The Mesentery is a double layer of the peri- 

 toneum which is reflected from the dorsal wall of the 

 abdomen, and encloses the stomach and intestines. 

 Blood-vessels, nerves, and lymphatics pass to the in- 

 testines between its two layers. 



d. The Qe;cum is seen at the point where the small 

 intestine passes into the large ; it is a coiled diverticu- 

 lum of the intestine two or more inches in length. 



e. The Large Intestine commences at the cEecum. 

 The first portion is known as the colon ; it passes an- 

 teriorly for a short distance as the ascending colon, 

 then transversely, the transverse colon, and finally 

 posteriorly as the descending colon, which is continued 

 directly into 



f. The Rectum. This is the terminal portion of the 

 large intestine ; it lies within the pelvis, and opens 

 to the exterior through the anus. 



g. Pev'er's Patches. At intervals along the lower 

 portion of the small intestine, on the border oppo- 

 site the attachment of the mesentery, a number of 

 small oval bodies will be seen, the Peyer's patches. 

 They are masses of lymphoid tissue imbedded in 

 the intestinal wall. 



h. Lymph Glands. Enclosed within the layers of 

 the mesentery will be found a number of lymph glands, 

 flattened oval bodies varying in size. Where the 



